# Source code for fontTools.subset

    # Copyright 2013 Google, Inc. All Rights Reserved.
    #
    # Google Author(s): Behdad Esfahbod

    from fontTools import config
    from fontTools.misc.roundTools import otRound
    from fontTools import ttLib
    from fontTools.ttLib.tables import otTables
    from fontTools.ttLib.tables.otBase import USE_HARFBUZZ_REPACKER
    from fontTools.otlLib.maxContextCalc import maxCtxFont
    from fontTools.pens.basePen import NullPen
    from fontTools.misc.loggingTools import Timer
    from fontTools.misc.cliTools import makeOutputFileName
    from fontTools.subset.util import _add_method, _uniq_sort
    from fontTools.subset.cff import *
    from fontTools.subset.svg import *
    from fontTools.varLib import varStore  # for subset_varidxes
    import sys
    import struct
    import array
    import logging
    from collections import Counter, defaultdict
    from functools import reduce
    from types import MethodType

    __usage__ = "pyftsubset font-file [glyph...] [--option=value]..."

    __doc__="""\
    pyftsubset -- OpenType font subsetter and optimizer

    pyftsubset is an OpenType font subsetter and optimizer, based on fontTools.
    It accepts any TT- or CFF-flavored OpenType (.otf or .ttf) or WOFF (.woff)
    font file. The subsetted glyph set is based on the specified glyphs
    or characters, and specified OpenType layout features.

    The tool also performs some size-reducing optimizations, aimed for using
    subset fonts as webfonts.  Individual optimizations can be enabled or
    disabled, and are enabled by default when they are safe.

    Usage: """+__usage__+"""

    At least one glyph or one of --gids, --gids-file, --glyphs, --glyphs-file,
    --text, --text-file, --unicodes, or --unicodes-file, must be specified.

    Args:

    font-file
      The input font file.
    glyph
      Specify one or more glyph identifiers to include in the subset. Must be
      PS glyph names, or the special string '*' to keep the entire glyph set.

    Initial glyph set specification
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    These options populate the initial glyph set. Same option can appear
    multiple times, and the results are accummulated.

    --gids=<NNN>[,<NNN>...]
      Specify comma/whitespace-separated list of glyph IDs or ranges as decimal
      numbers.  For example, --gids=10-12,14 adds glyphs with numbers 10, 11,
      12, and 14.

    --gids-file=<path>
      Like --gids but reads from a file. Anything after a '#' on any line is
      ignored as comments.

    --glyphs=<glyphname>[,<glyphname>...]
      Specify comma/whitespace-separated PS glyph names to add to the subset.
      Note that only PS glyph names are accepted, not gidNNN, U+XXXX, etc
      that are accepted on the command line.  The special string '*' will keep
      the entire glyph set.

    --glyphs-file=<path>
      Like --glyphs but reads from a file. Anything after a '#' on any line
      is ignored as comments.

    --text=<text>
      Specify characters to include in the subset, as UTF-8 string.

    --text-file=<path>
      Like --text but reads from a file. Newline character are not added to
      the subset.

    --unicodes=<XXXX>[,<XXXX>...]
      Specify comma/whitespace-separated list of Unicode codepoints or
      ranges as hex numbers, optionally prefixed with 'U+', 'u', etc.
      For example, --unicodes=41-5a,61-7a adds ASCII letters, so does
      the more verbose --unicodes=U+0041-005A,U+0061-007A.
      The special strings '*' will choose all Unicode characters mapped
      by the font.

    --unicodes-file=<path>
      Like --unicodes, but reads from a file. Anything after a '#' on any
      line in the file is ignored as comments.

    --ignore-missing-glyphs
      Do not fail if some requested glyphs or gids are not available in
      the font.

    --no-ignore-missing-glyphs
      Stop and fail if some requested glyphs or gids are not available
      in the font. [default]

    --ignore-missing-unicodes [default]
      Do not fail if some requested Unicode characters (including those
      indirectly specified using --text or --text-file) are not available
      in the font.

    --no-ignore-missing-unicodes
      Stop and fail if some requested Unicode characters are not available
      in the font.
      Note the default discrepancy between ignoring missing glyphs versus
      unicodes.  This is for historical reasons and in the future
      --no-ignore-missing-unicodes might become default.

    Other options
    ^^^^^^^^^^^^^

    For the other options listed below, to see the current value of the option,
    pass a value of '?' to it, with or without a '='.

    Examples::

        $ pyftsubset --glyph-names?
        Current setting for 'glyph-names' is: False
        $ ./pyftsubset --name-IDs=?
        Current setting for 'name-IDs' is: [0, 1, 2, 3, 4, 5, 6]
        $ ./pyftsubset --hinting? --no-hinting --hinting?
        Current setting for 'hinting' is: True
        Current setting for 'hinting' is: False

    Output options
    ^^^^^^^^^^^^^^

    --output-file=<path>
      The output font file. If not specified, the subsetted font
      will be saved in as font-file.subset.

    --flavor=<type>
      Specify flavor of output font file. May be 'woff' or 'woff2'.
      Note that WOFF2 requires the Brotli Python extension, available
      at https://github.com/google/brotli

    --with-zopfli
      Use the Google Zopfli algorithm to compress WOFF. The output is 3-8 %
      smaller than pure zlib, but the compression speed is much slower.
      The Zopfli Python bindings are available at:
      https://pypi.python.org/pypi/zopfli

    --harfbuzz-repacker
      By default, we serialize GPOS/GSUB using the HarfBuzz Repacker when
      uharfbuzz can be imported and is successful, otherwise fall back to
      the pure-python serializer. Set the option to force using the HarfBuzz
      Repacker (raises an error if uharfbuzz can't be found or fails).

    --no-harfbuzz-repacker
      Always use the pure-python serializer even if uharfbuzz is available.

    Glyph set expansion
    ^^^^^^^^^^^^^^^^^^^

    These options control how additional glyphs are added to the subset.

    --retain-gids
      Retain glyph indices; just empty glyphs not needed in-place.

    --notdef-glyph
      Add the '.notdef' glyph to the subset (ie, keep it). [default]

    --no-notdef-glyph
      Drop the '.notdef' glyph unless specified in the glyph set. This
      saves a few bytes, but is not possible for Postscript-flavored
      fonts, as those require '.notdef'. For TrueType-flavored fonts,
      this works fine as long as no unsupported glyphs are requested
      from the font.

    --notdef-outline
      Keep the outline of '.notdef' glyph. The '.notdef' glyph outline is
      used when glyphs not supported by the font are to be shown. It is not
      needed otherwise.

    --no-notdef-outline
      When including a '.notdef' glyph, remove its outline. This saves
      a few bytes. [default]

    --recommended-glyphs
      Add glyphs 0, 1, 2, and 3 to the subset, as recommended for
      TrueType-flavored fonts: '.notdef', 'NULL' or '.null', 'CR', 'space'.
      Some legacy software might require this, but no modern system does.

    --no-recommended-glyphs
      Do not add glyphs 0, 1, 2, and 3 to the subset, unless specified in
      glyph set. [default]

    --no-layout-closure
      Do not expand glyph set to add glyphs produced by OpenType layout
      features.  Instead, OpenType layout features will be subset to only
      rules that are relevant to the otherwise-specified glyph set.

    --layout-features[+|-]=<feature>[,<feature>...]
      Specify (=), add to (+=) or exclude from (-=) the comma-separated
      set of OpenType layout feature tags that will be preserved.
      Glyph variants used by the preserved features are added to the
      specified subset glyph set. By default, 'calt', 'ccmp', 'clig', 'curs',
      'dnom', 'frac', 'kern', 'liga', 'locl', 'mark', 'mkmk', 'numr', 'rclt',
      'rlig', 'rvrn', and all features required for script shaping are
      preserved. To see the full list, try '--layout-features=?'.
      Use '*' to keep all features.
      Multiple --layout-features options can be provided if necessary.
      Examples:

        --layout-features+=onum,pnum,ss01
            * Keep the default set of features and 'onum', 'pnum', 'ss01'.
        --layout-features-='mark','mkmk'
            * Keep the default set of features but drop 'mark' and 'mkmk'.
        --layout-features='kern'
            * Only keep the 'kern' feature, drop all others.
        --layout-features=''
            * Drop all features.
        --layout-features='*'
            * Keep all features.
        --layout-features+=aalt --layout-features-=vrt2
            * Keep default set of features plus 'aalt', but drop 'vrt2'.

    --layout-scripts[+|-]=<script>[,<script>...]
      Specify (=), add to (+=) or exclude from (-=) the comma-separated
      set of OpenType layout script tags that will be preserved. LangSys tags
      can be appended to script tag, separated by '.', for example:
      'arab.dflt,arab.URD,latn.TRK'. By default all scripts are retained ('*').

    Hinting options
    ^^^^^^^^^^^^^^^

    --hinting
      Keep hinting [default]

    --no-hinting
      Drop glyph-specific hinting and font-wide hinting tables, as well
      as remove hinting-related bits and pieces from other tables (eg. GPOS).
      See --hinting-tables for list of tables that are dropped by default.
      Instructions and hints are stripped from 'glyf' and 'CFF ' tables
      respectively. This produces (sometimes up to 30%) smaller fonts that
      are suitable for extremely high-resolution systems, like high-end
      mobile devices and retina displays.

    Optimization options
    ^^^^^^^^^^^^^^^^^^^^

    --desubroutinize
      Remove CFF use of subroutinizes.  Subroutinization is a way to make CFF
      fonts smaller.  For small subsets however, desubroutinizing might make
      the font smaller.  It has even been reported that desubroutinized CFF
      fonts compress better (produce smaller output) WOFF and WOFF2 fonts.
      Also see note under --no-hinting.

    --no-desubroutinize [default]
      Leave CFF subroutinizes as is, only throw away unused subroutinizes.

    Font table options
    ^^^^^^^^^^^^^^^^^^

    --drop-tables[+|-]=<table>[,<table>...]
      Specify (=), add to (+=) or exclude from (-=) the comma-separated
      set of tables that will be be dropped.
      By default, the following tables are dropped:
      'BASE', 'JSTF', 'DSIG', 'EBDT', 'EBLC', 'EBSC', 'PCLT', 'LTSH'
      and Graphite tables: 'Feat', 'Glat', 'Gloc', 'Silf', 'Sill'.
      The tool will attempt to subset the remaining tables.

      Examples:

      --drop-tables-='BASE'
          * Drop the default set of tables but keep 'BASE'.

      --drop-tables+=GSUB
          * Drop the default set of tables and 'GSUB'.

      --drop-tables=DSIG
          * Only drop the 'DSIG' table, keep all others.

      --drop-tables=
          * Keep all tables.

    --no-subset-tables+=<table>[,<table>...]
      Add to the set of tables that will not be subsetted.
      By default, the following tables are included in this list, as
      they do not need subsetting (ignore the fact that 'loca' is listed
      here): 'gasp', 'head', 'hhea', 'maxp', 'vhea', 'OS/2', 'loca', 'name',
      'cvt ', 'fpgm', 'prep', 'VMDX', 'DSIG', 'CPAL', 'MVAR', 'cvar', 'STAT'.
      By default, tables that the tool does not know how to subset and are not
      specified here will be dropped from the font, unless --passthrough-tables
      option is passed.

      Example:

       --no-subset-tables+=FFTM
          * Keep 'FFTM' table in the font by preventing subsetting.

    --passthrough-tables
      Do not drop tables that the tool does not know how to subset.

    --no-passthrough-tables
      Tables that the tool does not know how to subset and are not specified
      in --no-subset-tables will be dropped from the font. [default]

    --hinting-tables[-]=<table>[,<table>...]
      Specify (=), add to (+=) or exclude from (-=) the list of font-wide
      hinting tables that will be dropped if --no-hinting is specified.

      Examples:

      --hinting-tables-='VDMX'
          * Drop font-wide hinting tables except 'VDMX'.
      --hinting-tables=''
          * Keep all font-wide hinting tables (but strip hints from glyphs).

    --legacy-kern
      Keep TrueType 'kern' table even when OpenType 'GPOS' is available.

    --no-legacy-kern
      Drop TrueType 'kern' table if OpenType 'GPOS' is available. [default]

    Font naming options
    ^^^^^^^^^^^^^^^^^^^

    These options control what is retained in the 'name' table. For numerical
    codes, see: http://www.microsoft.com/typography/otspec/name.htm

    --name-IDs[+|-]=<nameID>[,<nameID>...]
      Specify (=), add to (+=) or exclude from (-=) the set of 'name' table
      entry nameIDs that will be preserved. By default, only nameIDs between 0
      and 6 are preserved, the rest are dropped. Use '*' to keep all entries.

      Examples:

      --name-IDs+=7,8,9
          * Also keep Trademark, Manufacturer and Designer name entries.
      --name-IDs=''
          * Drop all 'name' table entries.
      --name-IDs='*'
          * keep all 'name' table entries

    --name-legacy
      Keep legacy (non-Unicode) 'name' table entries (0.x, 1.x etc.).
      XXX Note: This might be needed for some fonts that have no Unicode name
      entires for English. See: https://github.com/fonttools/fonttools/issues/146

    --no-name-legacy
      Drop legacy (non-Unicode) 'name' table entries [default]

    --name-languages[+|-]=<langID>[,<langID>]
      Specify (=), add to (+=) or exclude from (-=) the set of 'name' table
      langIDs that will be preserved. By default only records with langID
      0x0409 (English) are preserved. Use '*' to keep all langIDs.

    --obfuscate-names
      Make the font unusable as a system font by replacing name IDs 1, 2, 3, 4,
      and 6 with dummy strings (it is still fully functional as webfont).

    Glyph naming and encoding options
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    --glyph-names
      Keep PS glyph names in TT-flavored fonts. In general glyph names are
      not needed for correct use of the font. However, some PDF generators
      and PDF viewers might rely on glyph names to extract Unicode text
      from PDF documents.
    --no-glyph-names
      Drop PS glyph names in TT-flavored fonts, by using 'post' table
      version 3.0. [default]
    --legacy-cmap
      Keep the legacy 'cmap' subtables (0.x, 1.x, 4.x etc.).
    --no-legacy-cmap
      Drop the legacy 'cmap' subtables. [default]
    --symbol-cmap
      Keep the 3.0 symbol 'cmap'.
    --no-symbol-cmap
      Drop the 3.0 symbol 'cmap'. [default]

    Other font-specific options
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^

    --recalc-bounds
        Recalculate font bounding boxes.
    --no-recalc-bounds
        Keep original font bounding boxes. This is faster and still safe
        for all practical purposes. [default]
    --recalc-timestamp
        Set font 'modified' timestamp to current time.
    --no-recalc-timestamp
        Do not modify font 'modified' timestamp. [default]
    --canonical-order
        Order tables as recommended in the OpenType standard. This is not
        required by the standard, nor by any known implementation.
    --no-canonical-order
        Keep original order of font tables. This is faster. [default]
    --prune-unicode-ranges
        Update the 'OS/2 ulUnicodeRange*' bits after subsetting. The Unicode
        ranges defined in the OpenType specification v1.7 are intersected with
        the Unicode codepoints specified in the font's Unicode 'cmap' subtables:
        when no overlap is found, the bit will be switched off. However, it will
        *not* be switched on if an intersection is found.  [default]
    --no-prune-unicode-ranges
        Don't change the 'OS/2 ulUnicodeRange*' bits.
    --recalc-average-width
        Update the 'OS/2 xAvgCharWidth' field after subsetting.
    --no-recalc-average-width
        Don't change the 'OS/2 xAvgCharWidth' field. [default]
    --recalc-max-context
        Update the 'OS/2 usMaxContext' field after subsetting.
    --no-recalc-max-context
        Don't change the 'OS/2 usMaxContext' field. [default]
    --font-number=<number>
        Select font number for TrueType Collection (.ttc/.otc), starting from 0.
    --pretty-svg
        When subsetting SVG table, use lxml pretty_print=True option to indent
        the XML output (only recommended for debugging purposes).

    Application options
    ^^^^^^^^^^^^^^^^^^^

    --verbose
        Display verbose information of the subsetting process.
    --timing
        Display detailed timing information of the subsetting process.
    --xml
        Display the TTX XML representation of subsetted font.

    Example
    ^^^^^^^

    Produce a subset containing the characters ' !"#$%' without performing
    size-reducing optimizations::

      $ pyftsubset font.ttf --unicodes="U+0020-0025" \\
        --layout-features='*' --glyph-names --symbol-cmap --legacy-cmap \\
        --notdef-glyph --notdef-outline --recommended-glyphs \\
        --name-IDs='*' --name-legacy --name-languages='*'
    """

    log = logging.getLogger("fontTools.subset")

    def _log_glyphs(self, glyphs, font=None):
    	self.info("Glyph names: %s", sorted(glyphs))
    	if font:
    		reverseGlyphMap = font.getReverseGlyphMap()
    		self.info("Glyph IDs:   %s", sorted(reverseGlyphMap[g] for g in glyphs))

    # bind "glyphs" function to 'log' object
    log.glyphs = MethodType(_log_glyphs, log)

    # I use a different timing channel so I can configure it separately from the
    # main module's logger
    timer = Timer(logger=logging.getLogger("fontTools.subset.timer"))

    def _dict_subset(d, glyphs):
    	return {g:d[g] for g in glyphs}

    def _list_subset(l, indices):
    	count = len(l)
    	return [l[i] for i in indices if i < count]

    @_add_method(otTables.Coverage)
    def intersect(self, glyphs):
    	"""Returns ascending list of matching coverage values."""
    	return [i for i,g in enumerate(self.glyphs) if g in glyphs]

    @_add_method(otTables.Coverage)
    def intersect_glyphs(self, glyphs):
    	"""Returns set of intersecting glyphs."""
    	return set(g for g in self.glyphs if g in glyphs)

    @_add_method(otTables.Coverage)
    def subset(self, glyphs):
    	"""Returns ascending list of remaining coverage values."""
    	indices = self.intersect(glyphs)
    	self.glyphs = [g for g in self.glyphs if g in glyphs]
    	return indices

    @_add_method(otTables.Coverage)
    def remap(self, coverage_map):
    	"""Remaps coverage."""
    	self.glyphs = [self.glyphs[i] for i in coverage_map]

    @_add_method(otTables.ClassDef)
    def intersect(self, glyphs):
    	"""Returns ascending list of matching class values."""
    	return _uniq_sort(
    		 ([0] if any(g not in self.classDefs for g in glyphs) else []) +
    			[v for g,v in self.classDefs.items() if g in glyphs])

    @_add_method(otTables.ClassDef)
    def intersect_class(self, glyphs, klass):
    	"""Returns set of glyphs matching class."""
    	if klass == 0:
    		return set(g for g in glyphs if g not in self.classDefs)
    	return set(g for g,v in self.classDefs.items()
    		     if v == klass and g in glyphs)

    @_add_method(otTables.ClassDef)
    def subset(self, glyphs, remap=False, useClass0=True):
    	"""Returns ascending list of remaining classes."""
    	self.classDefs = {g:v for g,v in self.classDefs.items() if g in glyphs}
    	# Note: while class 0 has the special meaning of "not matched",
    	# if no glyph will ever /not match/, we can optimize class 0 out too.
    	# Only do this if allowed.
    	indices = _uniq_sort(
    		 ([0] if ((not useClass0) or any(g not in self.classDefs for g in glyphs)) else []) +
    			list(self.classDefs.values()))
    	if remap:
    		self.remap(indices)
    	return indices

    @_add_method(otTables.ClassDef)
    def remap(self, class_map):
    	"""Remaps classes."""
    	self.classDefs = {g:class_map.index(v) for g,v in self.classDefs.items()}

    @_add_method(otTables.SingleSubst)
    def closure_glyphs(self, s, cur_glyphs):
    	s.glyphs.update(v for g,v in self.mapping.items() if g in cur_glyphs)

    @_add_method(otTables.SingleSubst)
    def subset_glyphs(self, s):
    	self.mapping = {g:v for g,v in self.mapping.items()
    					if g in s.glyphs and v in s.glyphs}
    	return bool(self.mapping)

    @_add_method(otTables.MultipleSubst)
    def closure_glyphs(self, s, cur_glyphs):
    	for glyph, subst in self.mapping.items():
    		if glyph in cur_glyphs:
    			s.glyphs.update(subst)

    @_add_method(otTables.MultipleSubst)
    def subset_glyphs(self, s):
    	self.mapping = {g:v for g,v in self.mapping.items()
    					if g in s.glyphs and all(sub in s.glyphs for sub in v)}
    	return bool(self.mapping)

    @_add_method(otTables.AlternateSubst)
    def closure_glyphs(self, s, cur_glyphs):
    	s.glyphs.update(*(vlist for g,vlist in self.alternates.items()
    				if g in cur_glyphs))

    @_add_method(otTables.AlternateSubst)
    def subset_glyphs(self, s):
    	self.alternates = {g:[v for v in vlist if v in s.glyphs]
    					   for g,vlist in self.alternates.items()
    					   if g in s.glyphs and
    					   any(v in s.glyphs for v in vlist)}
    	return bool(self.alternates)

    @_add_method(otTables.LigatureSubst)
    def closure_glyphs(self, s, cur_glyphs):
    	s.glyphs.update(*([seq.LigGlyph for seq in seqs
    					if all(c in s.glyphs for c in seq.Component)]
    			  for g,seqs in self.ligatures.items()
    			  if g in cur_glyphs))

    @_add_method(otTables.LigatureSubst)
    def subset_glyphs(self, s):
    	self.ligatures = {g:v for g,v in self.ligatures.items()
    					  if g in s.glyphs}
    	self.ligatures = {g:[seq for seq in seqs
    				 if seq.LigGlyph in s.glyphs and
    					all(c in s.glyphs for c in seq.Component)]
    			  for g,seqs in self.ligatures.items()}
    	self.ligatures = {g:v for g,v in self.ligatures.items() if v}
    	return bool(self.ligatures)

    @_add_method(otTables.ReverseChainSingleSubst)
    def closure_glyphs(self, s, cur_glyphs):
    	if self.Format == 1:
    		indices = self.Coverage.intersect(cur_glyphs)
    		if(not indices or
    		   not all(c.intersect(s.glyphs)
    				   for c in self.LookAheadCoverage + self.BacktrackCoverage)):
    			return
    		s.glyphs.update(self.Substitute[i] for i in indices)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ReverseChainSingleSubst)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		indices = self.Coverage.subset(s.glyphs)
    		self.Substitute = _list_subset(self.Substitute, indices)
    		# Now drop rules generating glyphs we don't want
    		indices = [i for i,sub in enumerate(self.Substitute)
    				 if sub in s.glyphs]
    		self.Substitute = _list_subset(self.Substitute, indices)
    		self.Coverage.remap(indices)
    		self.GlyphCount = len(self.Substitute)
    		return bool(self.GlyphCount and
    			    all(c.subset(s.glyphs)
    				for c in self.LookAheadCoverage+self.BacktrackCoverage))
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.Device)
    def is_hinting(self):
    	return self.DeltaFormat in (1,2,3)

    @_add_method(otTables.ValueRecord)
    def prune_hints(self):
    	for name in ['XPlaDevice', 'YPlaDevice', 'XAdvDevice', 'YAdvDevice']:
    		v = getattr(self, name, None)
    		if v is not None and v.is_hinting():
    			delattr(self, name)

    @_add_method(otTables.SinglePos)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		return len(self.Coverage.subset(s.glyphs))
    	elif self.Format == 2:
    		indices = self.Coverage.subset(s.glyphs)
    		values = self.Value
    		count = len(values)
    		self.Value = [values[i] for i in indices if i < count]
    		self.ValueCount = len(self.Value)
    		return bool(self.ValueCount)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.SinglePos)
    def prune_post_subset(self, font, options):
    	if self.Value is None:
    		assert self.ValueFormat == 0
    		return True

    	# Shrink ValueFormat
    	if self.Format == 1:
    		if not options.hinting:
    			self.Value.prune_hints()
    		self.ValueFormat = self.Value.getEffectiveFormat()
    	elif self.Format == 2:
    		if None in self.Value:
    			assert self.ValueFormat == 0
    			assert all(v is None for v in self.Value)
    		else:
    			if not options.hinting:
    				for v in self.Value:
    					v.prune_hints()
    			self.ValueFormat = reduce(
    				int.__or__, [v.getEffectiveFormat() for v in self.Value], 0
    			)

    	# Downgrade to Format 1 if all ValueRecords are the same
    	if self.Format == 2 and all(v == self.Value[0] for v in self.Value):
    		self.Format = 1
    		self.Value = self.Value[0] if self.ValueFormat != 0 else None
    		del self.ValueCount

    	return True

    @_add_method(otTables.PairPos)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		indices = self.Coverage.subset(s.glyphs)
    		pairs = self.PairSet
    		count = len(pairs)
    		self.PairSet = [pairs[i] for i in indices if i < count]
    		for p in self.PairSet:
    			p.PairValueRecord = [r for r in p.PairValueRecord if r.SecondGlyph in s.glyphs]
    			p.PairValueCount = len(p.PairValueRecord)
    		# Remove empty pairsets
    		indices = [i for i,p in enumerate(self.PairSet) if p.PairValueCount]
    		self.Coverage.remap(indices)
    		self.PairSet = _list_subset(self.PairSet, indices)
    		self.PairSetCount = len(self.PairSet)
    		return bool(self.PairSetCount)
    	elif self.Format == 2:
    		class1_map = [c for c in self.ClassDef1.subset(s.glyphs.intersection(self.Coverage.glyphs), remap=True) if c < self.Class1Count]
    		class2_map = [c for c in self.ClassDef2.subset(s.glyphs, remap=True, useClass0=False) if c < self.Class2Count]
    		self.Class1Record = [self.Class1Record[i] for i in class1_map]
    		for c in self.Class1Record:
    			c.Class2Record = [c.Class2Record[i] for i in class2_map]
    		self.Class1Count = len(class1_map)
    		self.Class2Count = len(class2_map)
    		# If only Class2 0 left, no need to keep anything.
    		return bool(self.Class1Count and
    					(self.Class2Count > 1) and
    					self.Coverage.subset(s.glyphs))
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.PairPos)
    def prune_post_subset(self, font, options):
    	if not options.hinting:
    		attr1, attr2 = {
    			1: ('PairSet', 'PairValueRecord'),
    			2: ('Class1Record', 'Class2Record'),
    		}[self.Format]

    		self.ValueFormat1 = self.ValueFormat2 = 0
    		for row in getattr(self, attr1):
    			for r in getattr(row, attr2):
    				if r.Value1:
    					r.Value1.prune_hints()
    					self.ValueFormat1 |= r.Value1.getEffectiveFormat()
    				if r.Value2:
    					r.Value2.prune_hints()
    					self.ValueFormat2 |= r.Value2.getEffectiveFormat()

    	return bool(self.ValueFormat1 | self.ValueFormat2)

    @_add_method(otTables.CursivePos)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		indices = self.Coverage.subset(s.glyphs)
    		records = self.EntryExitRecord
    		count = len(records)
    		self.EntryExitRecord = [records[i] for i in indices if i < count]
    		self.EntryExitCount = len(self.EntryExitRecord)
    		return bool(self.EntryExitCount)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.Anchor)
    def prune_hints(self):
    	if self.Format == 2:
    		self.Format = 1
    	elif self.Format == 3:
    		for name in ('XDeviceTable', 'YDeviceTable'):
    			v = getattr(self, name, None)
    			if v is not None and v.is_hinting():
    				setattr(self, name, None)
    		if self.XDeviceTable is None and self.YDeviceTable is None:
    			self.Format = 1

    @_add_method(otTables.CursivePos)
    def prune_post_subset(self, font, options):
    	if not options.hinting:
    		for rec in self.EntryExitRecord:
    			if rec.EntryAnchor: rec.EntryAnchor.prune_hints()
    			if rec.ExitAnchor: rec.ExitAnchor.prune_hints()
    	return True

    @_add_method(otTables.MarkBasePos)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		mark_indices = self.MarkCoverage.subset(s.glyphs)
    		self.MarkArray.MarkRecord = _list_subset(self.MarkArray.MarkRecord, mark_indices)
    		self.MarkArray.MarkCount = len(self.MarkArray.MarkRecord)
    		base_indices = self.BaseCoverage.subset(s.glyphs)
    		self.BaseArray.BaseRecord = _list_subset(self.BaseArray.BaseRecord, base_indices)
    		self.BaseArray.BaseCount = len(self.BaseArray.BaseRecord)
    		# Prune empty classes
    		class_indices = _uniq_sort(v.Class for v in self.MarkArray.MarkRecord)
    		self.ClassCount = len(class_indices)
    		for m in self.MarkArray.MarkRecord:
    			m.Class = class_indices.index(m.Class)
    		for b in self.BaseArray.BaseRecord:
    			b.BaseAnchor = _list_subset(b.BaseAnchor, class_indices)
    		return bool(self.ClassCount and
    			    self.MarkArray.MarkCount and
    			    self.BaseArray.BaseCount)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.MarkBasePos)
    def prune_post_subset(self, font, options):
    		if not options.hinting:
    			for m in self.MarkArray.MarkRecord:
    				if m.MarkAnchor:
    					m.MarkAnchor.prune_hints()
    			for b in self.BaseArray.BaseRecord:
    				for a in b.BaseAnchor:
    					if a:
    						a.prune_hints()
    		return True

    @_add_method(otTables.MarkLigPos)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		mark_indices = self.MarkCoverage.subset(s.glyphs)
    		self.MarkArray.MarkRecord = _list_subset(self.MarkArray.MarkRecord, mark_indices)
    		self.MarkArray.MarkCount = len(self.MarkArray.MarkRecord)
    		ligature_indices = self.LigatureCoverage.subset(s.glyphs)
    		self.LigatureArray.LigatureAttach = _list_subset(self.LigatureArray.LigatureAttach, ligature_indices)
    		self.LigatureArray.LigatureCount = len(self.LigatureArray.LigatureAttach)
    		# Prune empty classes
    		class_indices = _uniq_sort(v.Class for v in self.MarkArray.MarkRecord)
    		self.ClassCount = len(class_indices)
    		for m in self.MarkArray.MarkRecord:
    			m.Class = class_indices.index(m.Class)
    		for l in self.LigatureArray.LigatureAttach:
    			for c in l.ComponentRecord:
    				c.LigatureAnchor = _list_subset(c.LigatureAnchor, class_indices)
    		return bool(self.ClassCount and
    			    self.MarkArray.MarkCount and
    			    self.LigatureArray.LigatureCount)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.MarkLigPos)
    def prune_post_subset(self, font, options):
    		if not options.hinting:
    			for m in self.MarkArray.MarkRecord:
    				if m.MarkAnchor:
    					m.MarkAnchor.prune_hints()
    			for l in self.LigatureArray.LigatureAttach:
    				for c in l.ComponentRecord:
    					for a in c.LigatureAnchor:
    						if a:
    							a.prune_hints()
    		return True

    @_add_method(otTables.MarkMarkPos)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		mark1_indices = self.Mark1Coverage.subset(s.glyphs)
    		self.Mark1Array.MarkRecord = _list_subset(self.Mark1Array.MarkRecord, mark1_indices)
    		self.Mark1Array.MarkCount = len(self.Mark1Array.MarkRecord)
    		mark2_indices = self.Mark2Coverage.subset(s.glyphs)
    		self.Mark2Array.Mark2Record = _list_subset(self.Mark2Array.Mark2Record, mark2_indices)
    		self.Mark2Array.MarkCount = len(self.Mark2Array.Mark2Record)
    		# Prune empty classes
    		class_indices = _uniq_sort(v.Class for v in self.Mark1Array.MarkRecord)
    		self.ClassCount = len(class_indices)
    		for m in self.Mark1Array.MarkRecord:
    			m.Class = class_indices.index(m.Class)
    		for b in self.Mark2Array.Mark2Record:
    			b.Mark2Anchor = _list_subset(b.Mark2Anchor, class_indices)
    		return bool(self.ClassCount and
    			    self.Mark1Array.MarkCount and
    			    self.Mark2Array.MarkCount)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.MarkMarkPos)
    def prune_post_subset(self, font, options):
    		if not options.hinting:
    			for m in self.Mark1Array.MarkRecord:
    				if m.MarkAnchor:
    					m.MarkAnchor.prune_hints()
    			for b in self.Mark2Array.Mark2Record:
    				for m in b.Mark2Anchor:
    					if m:
    						m.prune_hints()
    		return True

    @_add_method(otTables.SingleSubst,
    			 otTables.MultipleSubst,
    			 otTables.AlternateSubst,
    			 otTables.LigatureSubst,
    			 otTables.ReverseChainSingleSubst,
    			 otTables.SinglePos,
    			 otTables.PairPos,
    			 otTables.CursivePos,
    			 otTables.MarkBasePos,
    			 otTables.MarkLigPos,
    			 otTables.MarkMarkPos)
    def subset_lookups(self, lookup_indices):
    	pass

    @_add_method(otTables.SingleSubst,
    			 otTables.MultipleSubst,
    			 otTables.AlternateSubst,
    			 otTables.LigatureSubst,
    			 otTables.ReverseChainSingleSubst,
    			 otTables.SinglePos,
    			 otTables.PairPos,
    			 otTables.CursivePos,
    			 otTables.MarkBasePos,
    			 otTables.MarkLigPos,
    			 otTables.MarkMarkPos)
    def collect_lookups(self):
    	return []

    @_add_method(otTables.SingleSubst,
    			 otTables.MultipleSubst,
    			 otTables.AlternateSubst,
    			 otTables.LigatureSubst,
    			 otTables.ReverseChainSingleSubst,
    			 otTables.ContextSubst,
    			 otTables.ChainContextSubst,
    			 otTables.ContextPos,
    			 otTables.ChainContextPos)
    def prune_post_subset(self, font, options):
    	return True

    @_add_method(otTables.SingleSubst,
    			 otTables.AlternateSubst,
    			 otTables.ReverseChainSingleSubst)
    def may_have_non_1to1(self):
    	return False

    @_add_method(otTables.MultipleSubst,
    			 otTables.LigatureSubst,
    			 otTables.ContextSubst,
    			 otTables.ChainContextSubst)
    def may_have_non_1to1(self):
    	return True

    @_add_method(otTables.ContextSubst,
    			 otTables.ChainContextSubst,
    			 otTables.ContextPos,
    			 otTables.ChainContextPos)
    def __subset_classify_context(self):

    	class ContextHelper(object):
    		def __init__(self, klass, Format):
    			if klass.__name__.endswith('Subst'):
    				Typ = 'Sub'
    				Type = 'Subst'
    			else:
    				Typ = 'Pos'
    				Type = 'Pos'
    			if klass.__name__.startswith('Chain'):
    				Chain = 'Chain'
    				InputIdx = 1
    				DataLen = 3
    			else:
    				Chain = ''
    				InputIdx = 0
    				DataLen = 1
    			ChainTyp = Chain+Typ

    			self.Typ = Typ
    			self.Type = Type
    			self.Chain = Chain
    			self.ChainTyp = ChainTyp
    			self.InputIdx = InputIdx
    			self.DataLen = DataLen

    			self.LookupRecord = Type+'LookupRecord'

    			if Format == 1:
    				Coverage = lambda r: r.Coverage
    				ChainCoverage = lambda r: r.Coverage
    				ContextData = lambda r:(None,)
    				ChainContextData = lambda r:(None, None, None)
    				SetContextData = None
    				SetChainContextData = None
    				RuleData = lambda r:(r.Input,)
    				ChainRuleData = lambda r:(r.Backtrack, r.Input, r.LookAhead)
    				def SetRuleData(r, d):
    					(r.Input,) = d
    					(r.GlyphCount,) = (len(x)+1 for x in d)
    				def ChainSetRuleData(r, d):
    					(r.Backtrack, r.Input, r.LookAhead) = d
    					(r.BacktrackGlyphCount,r.InputGlyphCount,r.LookAheadGlyphCount,) = (len(d[0]),len(d[1])+1,len(d[2]))
    			elif Format == 2:
    				Coverage = lambda r: r.Coverage
    				ChainCoverage = lambda r: r.Coverage
    				ContextData = lambda r:(r.ClassDef,)
    				ChainContextData = lambda r:(r.BacktrackClassDef,
    							     r.InputClassDef,
    							     r.LookAheadClassDef)
    				def SetContextData(r, d):
    					(r.ClassDef,) = d
    				def SetChainContextData(r, d):
    					(r.BacktrackClassDef,
    					 r.InputClassDef,
    					 r.LookAheadClassDef) = d
    				RuleData = lambda r:(r.Class,)
    				ChainRuleData = lambda r:(r.Backtrack, r.Input, r.LookAhead)
    				def SetRuleData(r, d):
    					(r.Class,) = d
    					(r.GlyphCount,) = (len(x)+1 for x in d)
    				def ChainSetRuleData(r, d):
    					(r.Backtrack, r.Input, r.LookAhead) = d
    					(r.BacktrackGlyphCount,r.InputGlyphCount,r.LookAheadGlyphCount,) = (len(d[0]),len(d[1])+1,len(d[2]))
    			elif Format == 3:
    				Coverage = lambda r: r.Coverage[0]
    				ChainCoverage = lambda r: r.InputCoverage[0]
    				ContextData = None
    				ChainContextData = None
    				SetContextData = None
    				SetChainContextData = None
    				RuleData = lambda r: r.Coverage
    				ChainRuleData = lambda r:(r.BacktrackCoverage +
    							  r.InputCoverage +
    							  r.LookAheadCoverage)
    				def SetRuleData(r, d):
    					(r.Coverage,) = d
    					(r.GlyphCount,) = (len(x) for x in d)
    				def ChainSetRuleData(r, d):
    					(r.BacktrackCoverage, r.InputCoverage, r.LookAheadCoverage) = d
    					(r.BacktrackGlyphCount,r.InputGlyphCount,r.LookAheadGlyphCount,) = (len(x) for x in d)
    			else:
    				assert 0, "unknown format: %s" % Format

    			if Chain:
    				self.Coverage = ChainCoverage
    				self.ContextData = ChainContextData
    				self.SetContextData = SetChainContextData
    				self.RuleData = ChainRuleData
    				self.SetRuleData = ChainSetRuleData
    			else:
    				self.Coverage = Coverage
    				self.ContextData = ContextData
    				self.SetContextData = SetContextData
    				self.RuleData = RuleData
    				self.SetRuleData = SetRuleData

    			if Format == 1:
    				self.Rule = ChainTyp+'Rule'
    				self.RuleCount = ChainTyp+'RuleCount'
    				self.RuleSet = ChainTyp+'RuleSet'
    				self.RuleSetCount = ChainTyp+'RuleSetCount'
    				self.Intersect = lambda glyphs, c, r: [r] if r in glyphs else []
    			elif Format == 2:
    				self.Rule = ChainTyp+'ClassRule'
    				self.RuleCount = ChainTyp+'ClassRuleCount'
    				self.RuleSet = ChainTyp+'ClassSet'
    				self.RuleSetCount = ChainTyp+'ClassSetCount'
    				self.Intersect = lambda glyphs, c, r: (c.intersect_class(glyphs, r) if c
    								       else (set(glyphs) if r == 0 else set()))

    				self.ClassDef = 'InputClassDef' if Chain else 'ClassDef'
    				self.ClassDefIndex = 1 if Chain else 0
    				self.Input = 'Input' if Chain else 'Class'
    			elif Format == 3:
    				self.Input = 'InputCoverage' if Chain else 'Coverage'

    	if self.Format not in [1, 2, 3]:
    		return None	# Don't shoot the messenger; let it go
    	if not hasattr(self.__class__, "_subset__ContextHelpers"):
    		self.__class__._subset__ContextHelpers = {}
    	if self.Format not in self.__class__._subset__ContextHelpers:
    		helper = ContextHelper(self.__class__, self.Format)
    		self.__class__._subset__ContextHelpers[self.Format] = helper
    	return self.__class__._subset__ContextHelpers[self.Format]

    @_add_method(otTables.ContextSubst,
    			 otTables.ChainContextSubst)
    def closure_glyphs(self, s, cur_glyphs):
    	c = self.__subset_classify_context()

    	indices = c.Coverage(self).intersect(cur_glyphs)
    	if not indices:
    		return []
    	cur_glyphs = c.Coverage(self).intersect_glyphs(cur_glyphs)

    	if self.Format == 1:
    		ContextData = c.ContextData(self)
    		rss = getattr(self, c.RuleSet)
    		rssCount = getattr(self, c.RuleSetCount)
    		for i in indices:
    			if i >= rssCount or not rss[i]: continue
    			for r in getattr(rss[i], c.Rule):
    				if not r: continue
    				if not all(all(c.Intersect(s.glyphs, cd, k) for k in klist)
    					   for cd,klist in zip(ContextData, c.RuleData(r))):
    					continue
    				chaos = set()
    				for ll in getattr(r, c.LookupRecord):
    					if not ll: continue
    					seqi = ll.SequenceIndex
    					if seqi in chaos:
    						# TODO Can we improve this?
    						pos_glyphs = None
    					else:
    						if seqi == 0:
    							pos_glyphs = frozenset([c.Coverage(self).glyphs[i]])
    						else:
    							pos_glyphs = frozenset([r.Input[seqi - 1]])
    					lookup = s.table.LookupList.Lookup[ll.LookupListIndex]
    					chaos.add(seqi)
    					if lookup.may_have_non_1to1():
    						chaos.update(range(seqi, len(r.Input)+2))
    					lookup.closure_glyphs(s, cur_glyphs=pos_glyphs)
    	elif self.Format == 2:
    		ClassDef = getattr(self, c.ClassDef)
    		indices = ClassDef.intersect(cur_glyphs)
    		ContextData = c.ContextData(self)
    		rss = getattr(self, c.RuleSet)
    		rssCount = getattr(self, c.RuleSetCount)
    		for i in indices:
    			if i >= rssCount or not rss[i]: continue
    			for r in getattr(rss[i], c.Rule):
    				if not r: continue
    				if not all(all(c.Intersect(s.glyphs, cd, k) for k in klist)
    						   for cd,klist in zip(ContextData, c.RuleData(r))):
    					continue
    				chaos = set()
    				for ll in getattr(r, c.LookupRecord):
    					if not ll: continue
    					seqi = ll.SequenceIndex
    					if seqi in chaos:
    						# TODO Can we improve this?
    						pos_glyphs = None
    					else:
    						if seqi == 0:
    							pos_glyphs = frozenset(ClassDef.intersect_class(cur_glyphs, i))
    						else:
    							pos_glyphs = frozenset(ClassDef.intersect_class(s.glyphs, getattr(r, c.Input)[seqi - 1]))
    					lookup = s.table.LookupList.Lookup[ll.LookupListIndex]
    					chaos.add(seqi)
    					if lookup.may_have_non_1to1():
    						chaos.update(range(seqi, len(getattr(r, c.Input))+2))
    					lookup.closure_glyphs(s, cur_glyphs=pos_glyphs)
    	elif self.Format == 3:
    		if not all(x is not None and x.intersect(s.glyphs) for x in c.RuleData(self)):
    			return []
    		r = self
    		input_coverages = getattr(r, c.Input)
    		chaos = set()
    		for ll in getattr(r, c.LookupRecord):
    			if not ll: continue
    			seqi = ll.SequenceIndex
    			if seqi in chaos:
    				# TODO Can we improve this?
    				pos_glyphs = None
    			else:
    				if seqi == 0:
    					pos_glyphs = frozenset(cur_glyphs)
    				else:
    					pos_glyphs = frozenset(input_coverages[seqi].intersect_glyphs(s.glyphs))
    			lookup = s.table.LookupList.Lookup[ll.LookupListIndex]
    			chaos.add(seqi)
    			if lookup.may_have_non_1to1():
    				chaos.update(range(seqi, len(input_coverages)+1))
    			lookup.closure_glyphs(s, cur_glyphs=pos_glyphs)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ContextSubst,
    			 otTables.ContextPos,
    			 otTables.ChainContextSubst,
    			 otTables.ChainContextPos)
    def subset_glyphs(self, s):
    	c = self.__subset_classify_context()

    	if self.Format == 1:
    		indices = self.Coverage.subset(s.glyphs)
    		rss = getattr(self, c.RuleSet)
    		rssCount = getattr(self, c.RuleSetCount)
    		rss = [rss[i] for i in indices if i < rssCount]
    		for rs in rss:
    			if not rs: continue
    			ss = getattr(rs, c.Rule)
    			ss = [r for r in ss
    				  if r and all(all(g in s.glyphs for g in glist)
    					       for glist in c.RuleData(r))]
    			setattr(rs, c.Rule, ss)
    			setattr(rs, c.RuleCount, len(ss))
    		# Prune empty rulesets
    		indices = [i for i,rs in enumerate(rss) if rs and getattr(rs, c.Rule)]
    		self.Coverage.remap(indices)
    		rss = _list_subset(rss, indices)
    		setattr(self, c.RuleSet, rss)
    		setattr(self, c.RuleSetCount, len(rss))
    		return bool(rss)
    	elif self.Format == 2:
    		if not self.Coverage.subset(s.glyphs):
    			return False
    		ContextData = c.ContextData(self)
    		klass_maps = [x.subset(s.glyphs, remap=True) if x else None for x in ContextData]

    		# Keep rulesets for class numbers that survived.
    		indices = klass_maps[c.ClassDefIndex]
    		rss = getattr(self, c.RuleSet)
    		rssCount = getattr(self, c.RuleSetCount)
    		rss = [rss[i] for i in indices if i < rssCount]
    		del rssCount
    		# Delete, but not renumber, unreachable rulesets.
    		indices = getattr(self, c.ClassDef).intersect(self.Coverage.glyphs)
    		rss = [rss if i in indices else None for i,rss in enumerate(rss)]

    		for rs in rss:
    			if not rs: continue
    			ss = getattr(rs, c.Rule)
    			ss = [r for r in ss
    				  if r and all(all(k in klass_map for k in klist)
    					       for klass_map,klist in zip(klass_maps, c.RuleData(r)))]
    			setattr(rs, c.Rule, ss)
    			setattr(rs, c.RuleCount, len(ss))

    			# Remap rule classes
    			for r in ss:
    				c.SetRuleData(r, [[klass_map.index(k) for k in klist]
    						  for klass_map,klist in zip(klass_maps, c.RuleData(r))])

    		# Prune empty rulesets
    		rss = [rs if rs and getattr(rs, c.Rule) else None for rs in rss]
    		while rss and rss[-1] is None:
    			del rss[-1]
    		setattr(self, c.RuleSet, rss)
    		setattr(self, c.RuleSetCount, len(rss))

    		# TODO: We can do a second round of remapping class values based
    		# on classes that are actually used in at least one rule.	Right
    		# now we subset classes to c.glyphs only.	Or better, rewrite
    		# the above to do that.

    		return bool(rss)
    	elif self.Format == 3:
    		return all(x is not None and x.subset(s.glyphs) for x in c.RuleData(self))
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ContextSubst,
    			 otTables.ChainContextSubst,
    			 otTables.ContextPos,
    			 otTables.ChainContextPos)
    def subset_lookups(self, lookup_indices):
    	c = self.__subset_classify_context()

    	if self.Format in [1, 2]:
    		for rs in getattr(self, c.RuleSet):
    			if not rs: continue
    			for r in getattr(rs, c.Rule):
    				if not r: continue
    				setattr(r, c.LookupRecord,
    					[ll for ll in getattr(r, c.LookupRecord)
    					 if ll and ll.LookupListIndex in lookup_indices])
    				for ll in getattr(r, c.LookupRecord):
    					if not ll: continue
    					ll.LookupListIndex = lookup_indices.index(ll.LookupListIndex)
    	elif self.Format == 3:
    		setattr(self, c.LookupRecord,
    				[ll for ll in getattr(self, c.LookupRecord)
    				 if ll and ll.LookupListIndex in lookup_indices])
    		for ll in getattr(self, c.LookupRecord):
    			if not ll: continue
    			ll.LookupListIndex = lookup_indices.index(ll.LookupListIndex)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ContextSubst,
    			 otTables.ChainContextSubst,
    			 otTables.ContextPos,
    			 otTables.ChainContextPos)
    def collect_lookups(self):
    	c = self.__subset_classify_context()

    	if self.Format in [1, 2]:
    		return [ll.LookupListIndex
    			for rs in getattr(self, c.RuleSet) if rs
    			for r in getattr(rs, c.Rule) if r
    			for ll in getattr(r, c.LookupRecord) if ll]
    	elif self.Format == 3:
    		return [ll.LookupListIndex
    			for ll in getattr(self, c.LookupRecord) if ll]
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ExtensionSubst)
    def closure_glyphs(self, s, cur_glyphs):
    	if self.Format == 1:
    		self.ExtSubTable.closure_glyphs(s, cur_glyphs)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ExtensionSubst)
    def may_have_non_1to1(self):
    	if self.Format == 1:
    		return self.ExtSubTable.may_have_non_1to1()
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ExtensionSubst,
    			 otTables.ExtensionPos)
    def subset_glyphs(self, s):
    	if self.Format == 1:
    		return self.ExtSubTable.subset_glyphs(s)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ExtensionSubst,
    			 otTables.ExtensionPos)
    def prune_post_subset(self, font, options):
    	if self.Format == 1:
    		return self.ExtSubTable.prune_post_subset(font, options)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ExtensionSubst,
    			 otTables.ExtensionPos)
    def subset_lookups(self, lookup_indices):
    	if self.Format == 1:
    		return self.ExtSubTable.subset_lookups(lookup_indices)
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.ExtensionSubst,
    			 otTables.ExtensionPos)
    def collect_lookups(self):
    	if self.Format == 1:
    		return self.ExtSubTable.collect_lookups()
    	else:
    		assert 0, "unknown format: %s" % self.Format

    @_add_method(otTables.Lookup)
    def closure_glyphs(self, s, cur_glyphs=None):
    	if cur_glyphs is None:
    		cur_glyphs = frozenset(s.glyphs)

    	# Memoize
    	key = id(self)
    	doneLookups = s._doneLookups
    	count,covered = doneLookups.get(key, (0, None))
    	if count != len(s.glyphs):
    		count,covered = doneLookups[key] = (len(s.glyphs), set())
    	if cur_glyphs.issubset(covered):
    		return
    	covered.update(cur_glyphs)

    	for st in self.SubTable:
    		if not st: continue
    		st.closure_glyphs(s, cur_glyphs)

    @_add_method(otTables.Lookup)
    def subset_glyphs(self, s):
    	self.SubTable = [st for st in self.SubTable if st and st.subset_glyphs(s)]
    	self.SubTableCount = len(self.SubTable)
    	return bool(self.SubTableCount)

    @_add_method(otTables.Lookup)
    def prune_post_subset(self, font, options):
    	ret = False
    	for st in self.SubTable:
    		if not st: continue
    		if st.prune_post_subset(font, options): ret = True
    	return ret

    @_add_method(otTables.Lookup)
    def subset_lookups(self, lookup_indices):
    	for s in self.SubTable:
    		s.subset_lookups(lookup_indices)

    @_add_method(otTables.Lookup)
    def collect_lookups(self):
    	return sum((st.collect_lookups() for st in self.SubTable if st), [])

    @_add_method(otTables.Lookup)
    def may_have_non_1to1(self):
    	return any(st.may_have_non_1to1() for st in self.SubTable if st)

    @_add_method(otTables.LookupList)
    def subset_glyphs(self, s):
    	"""Returns the indices of nonempty lookups."""
    	return [i for i,l in enumerate(self.Lookup) if l and l.subset_glyphs(s)]

    @_add_method(otTables.LookupList)
    def prune_post_subset(self, font, options):
    	ret = False
    	for l in self.Lookup:
    		if not l: continue
    		if l.prune_post_subset(font, options): ret = True
    	return ret

    @_add_method(otTables.LookupList)
    def subset_lookups(self, lookup_indices):
    	self.ensureDecompiled()
    	self.Lookup = [self.Lookup[i] for i in lookup_indices
    				   if i < self.LookupCount]
    	self.LookupCount = len(self.Lookup)
    	for l in self.Lookup:
    		l.subset_lookups(lookup_indices)

    @_add_method(otTables.LookupList)
    def neuter_lookups(self, lookup_indices):
    	"""Sets lookups not in lookup_indices to None."""
    	self.ensureDecompiled()
    	self.Lookup = [l if i in lookup_indices else None for i,l in enumerate(self.Lookup)]

    @_add_method(otTables.LookupList)
    def closure_lookups(self, lookup_indices):
    	"""Returns sorted index of all lookups reachable from lookup_indices."""
    	lookup_indices = _uniq_sort(lookup_indices)
    	recurse = lookup_indices
    	while True:
    		recurse_lookups = sum((self.Lookup[i].collect_lookups()
    				       for i in recurse if i < self.LookupCount), [])
    		recurse_lookups = [l for l in recurse_lookups
    				     if l not in lookup_indices and l < self.LookupCount]
    		if not recurse_lookups:
    			return _uniq_sort(lookup_indices)
    		recurse_lookups = _uniq_sort(recurse_lookups)
    		lookup_indices.extend(recurse_lookups)
    		recurse = recurse_lookups

    @_add_method(otTables.Feature)
    def subset_lookups(self, lookup_indices):
    	""""Returns True if feature is non-empty afterwards."""
    	self.LookupListIndex = [l for l in self.LookupListIndex
    				  if l in lookup_indices]
    	# Now map them.
    	self.LookupListIndex = [lookup_indices.index(l)
    				for l in self.LookupListIndex]
    	self.LookupCount = len(self.LookupListIndex)
    	# keep 'size' feature even if it contains no lookups; but drop any other
    	# empty feature (e.g. FeatureParams for stylistic set names)
    	# https://github.com/fonttools/fonttools/issues/2324
    	return (
    	  self.LookupCount or
    	  isinstance(self.FeatureParams, otTables.FeatureParamsSize)
    	)

    @_add_method(otTables.FeatureList)
    def subset_lookups(self, lookup_indices):
    	"""Returns the indices of nonempty features."""
    	# Note: Never ever drop feature 'pref', even if it's empty.
    	# HarfBuzz chooses shaper for Khmer based on presence of this
    	# feature.	See thread at:
    	# http://lists.freedesktop.org/archives/harfbuzz/2012-November/002660.html
    	return [i for i,f in enumerate(self.FeatureRecord)
    			if (f.Feature.subset_lookups(lookup_indices) or
    				f.FeatureTag == 'pref')]

    @_add_method(otTables.FeatureList)
    def collect_lookups(self, feature_indices):
    	return sum((self.FeatureRecord[i].Feature.LookupListIndex
    				for i in feature_indices
    				if i < self.FeatureCount), [])

    @_add_method(otTables.FeatureList)
    def subset_features(self, feature_indices):
    	self.ensureDecompiled()
    	self.FeatureRecord = _list_subset(self.FeatureRecord, feature_indices)
    	self.FeatureCount = len(self.FeatureRecord)
    	return bool(self.FeatureCount)

    @_add_method(otTables.FeatureTableSubstitution)
    def subset_lookups(self, lookup_indices):
    	"""Returns the indices of nonempty features."""
    	return [r.FeatureIndex for r in self.SubstitutionRecord
    			if r.Feature.subset_lookups(lookup_indices)]

    @_add_method(otTables.FeatureVariations)
    def subset_lookups(self, lookup_indices):
    	"""Returns the indices of nonempty features."""
    	return sum((f.FeatureTableSubstitution.subset_lookups(lookup_indices)
    				for f in self.FeatureVariationRecord), [])

    @_add_method(otTables.FeatureVariations)
    def collect_lookups(self, feature_indices):
    	return sum((r.Feature.LookupListIndex
    				for vr in self.FeatureVariationRecord
    				for r in vr.FeatureTableSubstitution.SubstitutionRecord
    				if r.FeatureIndex in feature_indices), [])

    @_add_method(otTables.FeatureTableSubstitution)
    def subset_features(self, feature_indices):
    	self.ensureDecompiled()
    	self.SubstitutionRecord = [r for r in self.SubstitutionRecord
    				     if r.FeatureIndex in feature_indices]
    	# remap feature indices
    	for r in self.SubstitutionRecord:
    		r.FeatureIndex = feature_indices.index(r.FeatureIndex)
    	self.SubstitutionCount = len(self.SubstitutionRecord)
    	return bool(self.SubstitutionCount)

    @_add_method(otTables.FeatureVariations)
    def subset_features(self, feature_indices):
    	self.ensureDecompiled()
    	for r in self.FeatureVariationRecord:
    		r.FeatureTableSubstitution.subset_features(feature_indices)
    	# Prune empty records at the end only
    	# https://github.com/fonttools/fonttools/issues/1881
    	while (self.FeatureVariationRecord and
    		not self.FeatureVariationRecord[-1]
    			.FeatureTableSubstitution.SubstitutionCount):
    		self.FeatureVariationRecord.pop()
    	self.FeatureVariationCount = len(self.FeatureVariationRecord)
    	return bool(self.FeatureVariationCount)

    @_add_method(otTables.DefaultLangSys,
    			 otTables.LangSys)
    def subset_features(self, feature_indices):
    	if self.ReqFeatureIndex in feature_indices:
    		self.ReqFeatureIndex = feature_indices.index(self.ReqFeatureIndex)
    	else:
    		self.ReqFeatureIndex = 65535
    	self.FeatureIndex = [f for f in self.FeatureIndex if f in feature_indices]
    	# Now map them.
    	self.FeatureIndex = [feature_indices.index(f) for f in self.FeatureIndex
    						      if f in feature_indices]
    	self.FeatureCount = len(self.FeatureIndex)
    	return bool(self.FeatureCount or self.ReqFeatureIndex != 65535)

    @_add_method(otTables.DefaultLangSys,
    			 otTables.LangSys)
    def collect_features(self):
    	feature_indices = self.FeatureIndex[:]
    	if self.ReqFeatureIndex != 65535:
    		feature_indices.append(self.ReqFeatureIndex)
    	return _uniq_sort(feature_indices)

    @_add_method(otTables.Script)
    def subset_features(self, feature_indices, keepEmptyDefaultLangSys=False):
    	if(self.DefaultLangSys and
    	   not self.DefaultLangSys.subset_features(feature_indices) and
    	   not keepEmptyDefaultLangSys):
    		self.DefaultLangSys = None
    	self.LangSysRecord = [l for l in self.LangSysRecord
    				if l.LangSys.subset_features(feature_indices)]
    	self.LangSysCount = len(self.LangSysRecord)
    	return bool(self.LangSysCount or self.DefaultLangSys)

    @_add_method(otTables.Script)
    def collect_features(self):
    	feature_indices = [l.LangSys.collect_features() for l in self.LangSysRecord]
    	if self.DefaultLangSys:
    		feature_indices.append(self.DefaultLangSys.collect_features())
    	return _uniq_sort(sum(feature_indices, []))

    @_add_method(otTables.ScriptList)
    def subset_features(self, feature_indices, retain_empty):
    	# https://bugzilla.mozilla.org/show_bug.cgi?id=1331737#c32
    	self.ScriptRecord = [s for s in self.ScriptRecord
    			       if s.Script.subset_features(feature_indices, s.ScriptTag=='DFLT') or
    				  retain_empty]
    	self.ScriptCount = len(self.ScriptRecord)
    	return bool(self.ScriptCount)

    @_add_method(otTables.ScriptList)
    def collect_features(self):
    	return _uniq_sort(sum((s.Script.collect_features()
    			       for s in self.ScriptRecord), []))

    # CBLC will inherit it
    @_add_method(ttLib.getTableClass('EBLC'))
    def subset_glyphs(self, s):
    	for strike in self.strikes:
    		for indexSubTable in strike.indexSubTables:
    			indexSubTable.names = [n for n in indexSubTable.names if n in s.glyphs]
    		strike.indexSubTables = [i for i in strike.indexSubTables if i.names]
    	self.strikes = [s for s in self.strikes if s.indexSubTables]

    	return True

    # CBDT will inherit it
    @_add_method(ttLib.getTableClass('EBDT'))
    def subset_glyphs(self, s):
    	strikeData = [
    		{g: strike[g] for g in s.glyphs if g in strike}
    		for strike in self.strikeData
    	]
    	# Prune empty strikes
    	# https://github.com/fonttools/fonttools/issues/1633
    	self.strikeData = [strike for strike in strikeData if strike]
    	return True

    @_add_method(ttLib.getTableClass('sbix'))
    def subset_glyphs(self, s):
    	for strike in self.strikes.values():
    		strike.glyphs = {g: strike.glyphs[g] for g in s.glyphs if g in strike.glyphs}

    	return True

    @_add_method(ttLib.getTableClass('GSUB'))
    def closure_glyphs(self, s):
    	s.table = self.table
    	if self.table.ScriptList:
    		feature_indices = self.table.ScriptList.collect_features()
    	else:
    		feature_indices = []
    	if self.table.FeatureList:
    		lookup_indices = self.table.FeatureList.collect_lookups(feature_indices)
    	else:
    		lookup_indices = []
    	if getattr(self.table, 'FeatureVariations', None):
    		lookup_indices += self.table.FeatureVariations.collect_lookups(feature_indices)
    	lookup_indices = _uniq_sort(lookup_indices)
    	if self.table.LookupList:
    		s._doneLookups = {}
    		while True:
    			orig_glyphs = frozenset(s.glyphs)
    			for i in lookup_indices:
    				if i >= self.table.LookupList.LookupCount: continue
    				if not self.table.LookupList.Lookup[i]: continue
    				self.table.LookupList.Lookup[i].closure_glyphs(s)
    			if orig_glyphs == s.glyphs:
    				break
    		del s._doneLookups
    	del s.table

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def subset_glyphs(self, s):
    	s.glyphs = s.glyphs_gsubed
    	if self.table.LookupList:
    		lookup_indices = self.table.LookupList.subset_glyphs(s)
    	else:
    		lookup_indices = []
    	self.subset_lookups(lookup_indices)
    	return True

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def retain_empty_scripts(self):
    	# https://github.com/fonttools/fonttools/issues/518
    	# https://bugzilla.mozilla.org/show_bug.cgi?id=1080739#c15
    	return self.__class__ == ttLib.getTableClass('GSUB')

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def subset_lookups(self, lookup_indices):
    	"""Retains specified lookups, then removes empty features, language
    	systems, and scripts."""
    	if self.table.LookupList:
    		self.table.LookupList.subset_lookups(lookup_indices)
    	if self.table.FeatureList:
    		feature_indices = self.table.FeatureList.subset_lookups(lookup_indices)
    	else:
    		feature_indices = []
    	if getattr(self.table, 'FeatureVariations', None):
    		feature_indices += self.table.FeatureVariations.subset_lookups(lookup_indices)
    	feature_indices = _uniq_sort(feature_indices)
    	if self.table.FeatureList:
    		self.table.FeatureList.subset_features(feature_indices)
    	if getattr(self.table, 'FeatureVariations', None):
    		self.table.FeatureVariations.subset_features(feature_indices)
    	if self.table.ScriptList:
    		self.table.ScriptList.subset_features(feature_indices, self.retain_empty_scripts())

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def neuter_lookups(self, lookup_indices):
    	"""Sets lookups not in lookup_indices to None."""
    	if self.table.LookupList:
    		self.table.LookupList.neuter_lookups(lookup_indices)

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def prune_lookups(self, remap=True):
    	"""Remove (default) or neuter unreferenced lookups"""
    	if self.table.ScriptList:
    		feature_indices = self.table.ScriptList.collect_features()
    	else:
    		feature_indices = []
    	if self.table.FeatureList:
    		lookup_indices = self.table.FeatureList.collect_lookups(feature_indices)
    	else:
    		lookup_indices = []
    	if getattr(self.table, 'FeatureVariations', None):
    		lookup_indices += self.table.FeatureVariations.collect_lookups(feature_indices)
    	lookup_indices = _uniq_sort(lookup_indices)
    	if self.table.LookupList:
    		lookup_indices = self.table.LookupList.closure_lookups(lookup_indices)
    	else:
    		lookup_indices = []
    	if remap:
    		self.subset_lookups(lookup_indices)
    	else:
    		self.neuter_lookups(lookup_indices)

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def subset_feature_tags(self, feature_tags):
    	if self.table.FeatureList:
    		feature_indices = \
    			[i for i,f in enumerate(self.table.FeatureList.FeatureRecord)
    			 if f.FeatureTag in feature_tags]
    		self.table.FeatureList.subset_features(feature_indices)
    		if getattr(self.table, 'FeatureVariations', None):
    			self.table.FeatureVariations.subset_features(feature_indices)
    	else:
    		feature_indices = []
    	if self.table.ScriptList:
    		self.table.ScriptList.subset_features(feature_indices, self.retain_empty_scripts())

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def subset_script_tags(self, tags):
    	langsys = {}
    	script_tags = set()
    	for tag in tags:
    		script_tag, lang_tag = tag.split(".") if "." in tag else (tag, '*')
    		script_tags.add(script_tag.ljust(4))
    		langsys.setdefault(script_tag, set()).add(lang_tag.ljust(4))

    	if self.table.ScriptList:
    		self.table.ScriptList.ScriptRecord = \
    			[s for s in self.table.ScriptList.ScriptRecord
    			 if s.ScriptTag in script_tags]
    		self.table.ScriptList.ScriptCount = len(self.table.ScriptList.ScriptRecord)

    		for record in self.table.ScriptList.ScriptRecord:
    			if record.ScriptTag in langsys and '*   ' not in langsys[record.ScriptTag]:
    				record.Script.LangSysRecord = \
    					[l for l in record.Script.LangSysRecord
    					 if l.LangSysTag in langsys[record.ScriptTag]]
    				record.Script.LangSysCount = len(record.Script.LangSysRecord)
    				if "dflt" not in langsys[record.ScriptTag]:
    					record.Script.DefaultLangSys = None

    @_add_method(ttLib.getTableClass('GSUB'),
    			 ttLib.getTableClass('GPOS'))
    def prune_features(self):
    	"""Remove unreferenced features"""
    	if self.table.ScriptList:
    		feature_indices = self.table.ScriptList.collect_features()
    	else:
    		feature_indices = []
    	if self.table.FeatureList:
    		self.table.FeatureList.subset_features(feature_indices)
    	if getattr(self.table, 'FeatureVariations', None):
    		self.table.FeatureVariations.subset_features(feature_indices)
    	if self.table.ScriptList:
    		self.table.ScriptList.subset_features(feature_indices, self.retain_empty_scripts())

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def prune_pre_subset(self, font, options):
    	# Drop undesired features
    	if '*' not in options.layout_scripts:
    		self.subset_script_tags(options.layout_scripts)
    	if '*' not in options.layout_features:
    		self.subset_feature_tags(options.layout_features)
    	# Neuter unreferenced lookups
    	self.prune_lookups(remap=False)
    	return True

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def remove_redundant_langsys(self):
    	table = self.table
    	if not table.ScriptList or not table.FeatureList:
    		return

    	features = table.FeatureList.FeatureRecord

    	for s in table.ScriptList.ScriptRecord:
    		d = s.Script.DefaultLangSys
    		if not d:
    			continue
    		for lr in s.Script.LangSysRecord[:]:
    			l = lr.LangSys
    			# Compare d and l
    			if len(d.FeatureIndex) != len(l.FeatureIndex):
    				continue
    			if (d.ReqFeatureIndex == 65535) != (l.ReqFeatureIndex == 65535):
    				continue

    			if d.ReqFeatureIndex != 65535:
    				if features[d.ReqFeatureIndex] != features[l.ReqFeatureIndex]:
    					continue

    			for i in range(len(d.FeatureIndex)):
    				if features[d.FeatureIndex[i]] != features[l.FeatureIndex[i]]:
    					break
    			else:
    				# LangSys and default are equal; delete LangSys
    				s.Script.LangSysRecord.remove(lr)

    @_add_method(ttLib.getTableClass('GSUB'),
    	     ttLib.getTableClass('GPOS'))
    def prune_post_subset(self, font, options):
    	table = self.table

    	self.prune_lookups() # XXX Is this actually needed?!

    	if table.LookupList:
    		table.LookupList.prune_post_subset(font, options)
    		# XXX Next two lines disabled because OTS is stupid and
    		# doesn't like NULL offsets here.
    		#if not table.LookupList.Lookup:
    		#	table.LookupList = None

    	if not table.LookupList:
    		table.FeatureList = None

    	if table.FeatureList:
    		self.remove_redundant_langsys()
    		# Remove unreferenced features
    		self.prune_features()

    	# XXX Next two lines disabled because OTS is stupid and
    	# doesn't like NULL offsets here.
    	#if table.FeatureList and not table.FeatureList.FeatureRecord:
    	#	table.FeatureList = None

    	# Never drop scripts themselves as them just being available
    	# holds semantic significance.
    	# XXX Next two lines disabled because OTS is stupid and
    	# doesn't like NULL offsets here.
    	#if table.ScriptList and not table.ScriptList.ScriptRecord:
    	#	table.ScriptList = None

    	if hasattr(table, 'FeatureVariations'):
    		# drop FeatureVariations if there are no features to substitute
    		if table.FeatureVariations and not (
    			table.FeatureList and table.FeatureVariations.FeatureVariationRecord
    		):
    			table.FeatureVariations = None

    		# downgrade table version if there are no FeatureVariations
    		if not table.FeatureVariations and table.Version == 0x00010001:
    			table.Version = 0x00010000

    	return True

    @_add_method(ttLib.getTableClass('GDEF'))
    def subset_glyphs(self, s):
    	glyphs = s.glyphs_gsubed
    	table = self.table
    	if table.LigCaretList:
    		indices = table.LigCaretList.Coverage.subset(glyphs)
    		table.LigCaretList.LigGlyph = _list_subset(table.LigCaretList.LigGlyph, indices)
    		table.LigCaretList.LigGlyphCount = len(table.LigCaretList.LigGlyph)
    	if table.MarkAttachClassDef:
    		table.MarkAttachClassDef.classDefs = \
    			{g:v for g,v in table.MarkAttachClassDef.classDefs.items()
    			 if g in glyphs}
    	if table.GlyphClassDef:
    		table.GlyphClassDef.classDefs = \
    			{g:v for g,v in table.GlyphClassDef.classDefs.items()
    			 if g in glyphs}
    	if table.AttachList:
    		indices = table.AttachList.Coverage.subset(glyphs)
    		GlyphCount = table.AttachList.GlyphCount
    		table.AttachList.AttachPoint = [table.AttachList.AttachPoint[i]
    						for i in indices if i < GlyphCount]
    		table.AttachList.GlyphCount = len(table.AttachList.AttachPoint)
    	if hasattr(table, "MarkGlyphSetsDef") and table.MarkGlyphSetsDef:
    		for coverage in table.MarkGlyphSetsDef.Coverage:
    			if coverage:
    				coverage.subset(glyphs)

    		# TODO: The following is disabled. If enabling, we need to go fixup all
    		# lookups that use MarkFilteringSet and map their set.
    		# indices = table.MarkGlyphSetsDef.Coverage = \
    		#   [c for c in table.MarkGlyphSetsDef.Coverage if c.glyphs]
    		# TODO: The following is disabled, as ots doesn't like it. Phew...
    		# https://github.com/khaledhosny/ots/issues/172
    		# table.MarkGlyphSetsDef.Coverage = [c if c.glyphs else None for c in table.MarkGlyphSetsDef.Coverage]
    	return True

    def _pruneGDEF(font):
    	if 'GDEF' not in font: return
    	gdef = font['GDEF']
    	table = gdef.table
    	if not hasattr(table, 'VarStore'): return

    	store = table.VarStore

    	usedVarIdxes = set()

    	# Collect.
    	table.collect_device_varidxes(usedVarIdxes)
    	if 'GPOS' in font:
    		font['GPOS'].table.collect_device_varidxes(usedVarIdxes)

    	# Subset.
    	varidx_map = store.subset_varidxes(usedVarIdxes)

    	# Map.
    	table.remap_device_varidxes(varidx_map)
    	if 'GPOS' in font:
    		font['GPOS'].table.remap_device_varidxes(varidx_map)

    @_add_method(ttLib.getTableClass('GDEF'))
    def prune_post_subset(self, font, options):
    	table = self.table
    	# XXX check these against OTS
    	if table.LigCaretList and not table.LigCaretList.LigGlyphCount:
    		table.LigCaretList = None
    	if table.MarkAttachClassDef and not table.MarkAttachClassDef.classDefs:
    		table.MarkAttachClassDef = None
    	if table.GlyphClassDef and not table.GlyphClassDef.classDefs:
    		table.GlyphClassDef = None
    	if table.AttachList and not table.AttachList.GlyphCount:
    		table.AttachList = None
    	if hasattr(table, "VarStore"):
    		_pruneGDEF(font)
    		if table.VarStore.VarDataCount == 0:
    			if table.Version == 0x00010003:
    				table.Version = 0x00010002
    	if (not hasattr(table, "MarkGlyphSetsDef") or
    		not table.MarkGlyphSetsDef or
    		not table.MarkGlyphSetsDef.Coverage):
    		table.MarkGlyphSetsDef = None
    		if table.Version == 0x00010002:
    			table.Version = 0x00010000
    	return bool(table.LigCaretList or
    		    table.MarkAttachClassDef or
    		    table.GlyphClassDef or
    		    table.AttachList or
    		    (table.Version >= 0x00010002 and table.MarkGlyphSetsDef) or
    		    (table.Version >= 0x00010003 and table.VarStore))

    @_add_method(ttLib.getTableClass('kern'))
    def prune_pre_subset(self, font, options):
    	# Prune unknown kern table types
    	self.kernTables = [t for t in self.kernTables if hasattr(t, 'kernTable')]
    	return bool(self.kernTables)

    @_add_method(ttLib.getTableClass('kern'))
    def subset_glyphs(self, s):
    	glyphs = s.glyphs_gsubed
    	for t in self.kernTables:
    		t.kernTable = {(a,b):v for (a,b),v in t.kernTable.items()
    				       if a in glyphs and b in glyphs}
    	self.kernTables = [t for t in self.kernTables if t.kernTable]
    	return bool(self.kernTables)

    @_add_method(ttLib.getTableClass('vmtx'))
    def subset_glyphs(self, s):
    	self.metrics = _dict_subset(self.metrics, s.glyphs)
    	for g in s.glyphs_emptied:
    		self.metrics[g] = (0,0)
    	return bool(self.metrics)

    @_add_method(ttLib.getTableClass('hmtx'))
    def subset_glyphs(self, s):
    	self.metrics = _dict_subset(self.metrics, s.glyphs)
    	for g in s.glyphs_emptied:
    		self.metrics[g] = (0,0)
    	return True # Required table

    @_add_method(ttLib.getTableClass('hdmx'))
    def subset_glyphs(self, s):
    	self.hdmx = {sz:_dict_subset(l, s.glyphs) for sz,l in self.hdmx.items()}
    	for sz in self.hdmx:
    		for g in s.glyphs_emptied:
    			self.hdmx[sz][g] = 0
    	return bool(self.hdmx)

    @_add_method(ttLib.getTableClass('ankr'))
    def subset_glyphs(self, s):
    	table = self.table.AnchorPoints
    	assert table.Format == 0, "unknown 'ankr' format %s" % table.Format
    	table.Anchors = {glyph: table.Anchors[glyph] for glyph in s.glyphs
    					 if glyph in table.Anchors}
    	return len(table.Anchors) > 0

    @_add_method(ttLib.getTableClass('bsln'))
    def closure_glyphs(self, s):
    	table = self.table.Baseline
    	if table.Format in (2, 3):
    		s.glyphs.add(table.StandardGlyph)

    @_add_method(ttLib.getTableClass('bsln'))
    def subset_glyphs(self, s):
    	table = self.table.Baseline
    	if table.Format in (1, 3):
    		baselines = {glyph: table.BaselineValues.get(glyph, table.DefaultBaseline)
    					 for glyph in s.glyphs}
    		if len(baselines) > 0:
    			mostCommon, _cnt = Counter(baselines.values()).most_common(1)[0]
    			table.DefaultBaseline = mostCommon
    			baselines = {glyph: b for glyph, b in baselines.items()
    					      if b != mostCommon}
    		if len(baselines) > 0:
    			table.BaselineValues = baselines
    		else:
    			table.Format = {1: 0, 3: 2}[table.Format]
    			del table.BaselineValues
    	return True

    @_add_method(ttLib.getTableClass('lcar'))
    def subset_glyphs(self, s):
    	table = self.table.LigatureCarets
    	if table.Format in (0, 1):
    		table.Carets = {glyph: table.Carets[glyph] for glyph in s.glyphs
    							   if glyph in table.Carets}
    		return len(table.Carets) > 0
    	else:
    		assert False, "unknown 'lcar' format %s" % table.Format

    @_add_method(ttLib.getTableClass('gvar'))
    def prune_pre_subset(self, font, options):
    	if options.notdef_glyph and not options.notdef_outline:
    		self.variations[font.glyphOrder[0]] = []
    	return True

    @_add_method(ttLib.getTableClass('gvar'))
    def subset_glyphs(self, s):
    	self.variations = _dict_subset(self.variations, s.glyphs)
    	self.glyphCount = len(self.variations)
    	return bool(self.variations)

    def _remap_index_map(s, varidx_map, table_map):
    	map_ = {k:varidx_map[v] for k,v in table_map.mapping.items()}
    	# Emptied glyphs are remapped to:
    	# if GID <= last retained GID, 0/0: delta set for 0/0 is expected to exist & zeros compress well
    	# if GID > last retained GID, major/minor of the last retained glyph: will be optimized out by table compiler
    	last_idx = varidx_map[table_map.mapping[s.last_retained_glyph]]
    	for g,i in s.reverseEmptiedGlyphMap.items():
    		map_[g] = last_idx if i > s.last_retained_order else 0
    	return map_

    @_add_method(ttLib.getTableClass('HVAR'))
    def subset_glyphs(self, s):
    	table = self.table

    	used = set()
    	advIdxes_ = set()
    	retainAdvMap = False

    	if table.AdvWidthMap:
    		table.AdvWidthMap.mapping = _dict_subset(table.AdvWidthMap.mapping, s.glyphs)
    		used.update(table.AdvWidthMap.mapping.values())
    	else:
    		used.update(s.reverseOrigGlyphMap.values())
    		advIdxes_ = used.copy()
    		retainAdvMap = s.options.retain_gids

    	if table.LsbMap:
    		table.LsbMap.mapping = _dict_subset(table.LsbMap.mapping, s.glyphs)
    		used.update(table.LsbMap.mapping.values())
    	if table.RsbMap:
    		table.RsbMap.mapping = _dict_subset(table.RsbMap.mapping, s.glyphs)
    		used.update(table.RsbMap.mapping.values())

    	varidx_map = table.VarStore.subset_varidxes(used, retainFirstMap=retainAdvMap, advIdxes=advIdxes_)

    	if table.AdvWidthMap:
    		table.AdvWidthMap.mapping = _remap_index_map(s, varidx_map, table.AdvWidthMap)
    	if table.LsbMap:
    		table.LsbMap.mapping = _remap_index_map(s, varidx_map, table.LsbMap)
    	if table.RsbMap:
    		table.RsbMap.mapping = _remap_index_map(s, varidx_map, table.RsbMap)

    	# TODO Return emptiness...
    	return True

    @_add_method(ttLib.getTableClass('VVAR'))
    def subset_glyphs(self, s):
    	table = self.table

    	used = set()
    	advIdxes_ = set()
    	retainAdvMap = False

    	if table.AdvHeightMap:
    		table.AdvHeightMap.mapping = _dict_subset(table.AdvHeightMap.mapping, s.glyphs)
    		used.update(table.AdvHeightMap.mapping.values())
    	else:
    		used.update(s.reverseOrigGlyphMap.values())
    		advIdxes_ = used.copy()
    		retainAdvMap = s.options.retain_gids

    	if table.TsbMap:
    		table.TsbMap.mapping = _dict_subset(table.TsbMap.mapping, s.glyphs)
    		used.update(table.TsbMap.mapping.values())
    	if table.BsbMap:
    		table.BsbMap.mapping = _dict_subset(table.BsbMap.mapping, s.glyphs)
    		used.update(table.BsbMap.mapping.values())
    	if table.VOrgMap:
    		table.VOrgMap.mapping = _dict_subset(table.VOrgMap.mapping, s.glyphs)
    		used.update(table.VOrgMap.mapping.values())

    	varidx_map = table.VarStore.subset_varidxes(used, retainFirstMap=retainAdvMap, advIdxes=advIdxes_)

    	if table.AdvHeightMap:
    		table.AdvHeightMap.mapping = _remap_index_map(s, varidx_map, table.AdvHeightMap)
    	if table.TsbMap:
    		table.TsbMap.mapping = _remap_index_map(s, varidx_map, table.TsbMap)
    	if table.BsbMap:
    		table.BsbMap.mapping = _remap_index_map(s, varidx_map, table.BsbMap)
    	if table.VOrgMap:
    		table.VOrgMap.mapping = _remap_index_map(s, varidx_map, table.VOrgMap)

    	# TODO Return emptiness...
    	return True

    @_add_method(ttLib.getTableClass('VORG'))
    def subset_glyphs(self, s):
    	self.VOriginRecords = {g:v for g,v in self.VOriginRecords.items()
    				   if g in s.glyphs}
    	self.numVertOriginYMetrics = len(self.VOriginRecords)
    	return True	# Never drop; has default metrics

    @_add_method(ttLib.getTableClass('opbd'))
    def subset_glyphs(self, s):
    	table = self.table.OpticalBounds
    	if table.Format == 0:
    		table.OpticalBoundsDeltas = {glyph: table.OpticalBoundsDeltas[glyph]
    					     for glyph in s.glyphs
    					     if glyph in table.OpticalBoundsDeltas}
    		return len(table.OpticalBoundsDeltas) > 0
    	elif table.Format == 1:
    		table.OpticalBoundsPoints = {glyph: table.OpticalBoundsPoints[glyph]
    					     for glyph in s.glyphs
    					     if glyph in table.OpticalBoundsPoints}
    		return len(table.OpticalBoundsPoints) > 0
    	else:
    		assert False, "unknown 'opbd' format %s" % table.Format

    @_add_method(ttLib.getTableClass('post'))
    def prune_pre_subset(self, font, options):
    	if not options.glyph_names:
    		self.formatType = 3.0
    	return True # Required table

    @_add_method(ttLib.getTableClass('post'))
    def subset_glyphs(self, s):
    	self.extraNames = []	# This seems to do it
    	return True # Required table

    @_add_method(ttLib.getTableClass('prop'))
    def subset_glyphs(self, s):
    	prop = self.table.GlyphProperties
    	if prop.Format == 0:
    		return prop.DefaultProperties != 0
    	elif prop.Format == 1:
    		prop.Properties = {g: prop.Properties.get(g, prop.DefaultProperties)
    				   for g in s.glyphs}
    		mostCommon, _cnt = Counter(prop.Properties.values()).most_common(1)[0]
    		prop.DefaultProperties = mostCommon
    		prop.Properties = {g: prop for g, prop in prop.Properties.items()
    				   if prop != mostCommon}
    		if len(prop.Properties) == 0:
    			del prop.Properties
    			prop.Format = 0
    			return prop.DefaultProperties != 0
    		return True
    	else:
    		assert False, "unknown 'prop' format %s" % prop.Format

    def _paint_glyph_names(paint, colr):
    	result = set()

    	def callback(paint):
    		if paint.Format in {
    			otTables.PaintFormat.PaintGlyph,
    			otTables.PaintFormat.PaintColrGlyph,
    		}:
    			result.add(paint.Glyph)

    	paint.traverse(colr, callback)
    	return result

    @_add_method(ttLib.getTableClass('COLR'))
    def closure_glyphs(self, s):
    	if self.version > 0:
    		# on decompiling COLRv1, we only keep around the raw otTables
    		# but for subsetting we need dicts with fully decompiled layers;
    		# we store them temporarily in the C_O_L_R_ instance and delete
    		# them after we have finished subsetting.
    		self.ColorLayers = self._decompileColorLayersV0(self.table)
    		self.ColorLayersV1 = {
    			rec.BaseGlyph: rec.Paint
    			for rec in self.table.BaseGlyphList.BaseGlyphPaintRecord
    		}

    	decompose = s.glyphs
    	while decompose:
    		layers = set()
    		for g in decompose:
    			for layer in self.ColorLayers.get(g, []):
    				layers.add(layer.name)

    			if self.version > 0:
    				paint = self.ColorLayersV1.get(g)
    				if paint is not None:
    					layers.update(_paint_glyph_names(paint, self.table))

    		layers -= s.glyphs
    		s.glyphs.update(layers)
    		decompose = layers

    @_add_method(ttLib.getTableClass('COLR'))
    def subset_glyphs(self, s):
    	from fontTools.colorLib.unbuilder import unbuildColrV1
    	from fontTools.colorLib.builder import buildColrV1, populateCOLRv0

    	# only include glyphs after COLR closure, which in turn comes after cmap and GSUB
    	# closure, but importantly before glyf/CFF closures. COLR layers can refer to
    	# composite glyphs, and that's ok, since glyf/CFF closures happen after COLR closure
    	# and take care of those. If we also included glyphs resulting from glyf/CFF closures
    	# when deciding which COLR base glyphs to retain, then we may end up with a situation
    	# whereby a COLR base glyph is kept, not because directly requested (cmap)
    	# or substituted (GSUB) or referenced by another COLRv1 PaintColrGlyph, but because
    	# it corresponds to (has same GID as) a non-COLR glyph that happens to be used as a
    	# component in glyf or CFF table. Best case scenario we retain more glyphs than
    	# required; worst case we retain incomplete COLR records that try to reference
    	# glyphs that are no longer in the final subset font.
    	# https://github.com/fonttools/fonttools/issues/2461
    	s.glyphs = s.glyphs_colred

    	self.ColorLayers = {g: self.ColorLayers[g] for g in s.glyphs if g in self.ColorLayers}
    	if self.version == 0:
    		return bool(self.ColorLayers)

    	colorGlyphsV1 = unbuildColrV1(self.table.LayerList, self.table.BaseGlyphList)
    	self.table.LayerList, self.table.BaseGlyphList = buildColrV1(
    		{g: colorGlyphsV1[g] for g in colorGlyphsV1 if g in s.glyphs}
    	)
    	del self.ColorLayersV1

    	if self.table.ClipList is not None:
    		clips = self.table.ClipList.clips
    		self.table.ClipList.clips = {g: clips[g] for g in clips if g in s.glyphs}

    	layersV0 = self.ColorLayers
    	if not self.table.BaseGlyphList.BaseGlyphPaintRecord:
    		# no more COLRv1 glyphs: downgrade to version 0
    		self.version = 0
    		del self.table
    		return bool(layersV0)

    	populateCOLRv0(
    		self.table,
    		{
    			g: [(layer.name, layer.colorID) for layer in layersV0[g]]
    			for g in layersV0
    		},
    	)
    	del self.ColorLayers

    	# TODO: also prune ununsed varIndices in COLR.VarStore
    	return True

    @_add_method(ttLib.getTableClass('CPAL'))
    def prune_post_subset(self, font, options):
    	# Keep whole "CPAL" if "SVG " is present as it may be referenced by the latter
    	# via 'var(--color{palette_entry_index}, ...)' CSS color variables.
    	# For now we just assume this is the case by the mere presence of "SVG " table,
    	# for parsing SVG to collect all the used indices is too much work...
    	# TODO(anthrotype): Do The Right Thing (TM).
    	if "SVG " in font:
    		return True

    	colr = font.get("COLR")
    	if not colr:  # drop CPAL if COLR was subsetted to empty
    		return False

    	colors_by_index = defaultdict(list)

    	def collect_colors_by_index(paint):
    		if hasattr(paint, "PaletteIndex"):  # either solid colors...
    			colors_by_index[paint.PaletteIndex].append(paint)
    		elif hasattr(paint, "ColorLine"):  # ... or gradient color stops
    			for stop in paint.ColorLine.ColorStop:
    				colors_by_index[stop.PaletteIndex].append(stop)

    	if colr.version == 0:
    		for layers in colr.ColorLayers.values():
    			for layer in layers:
    				colors_by_index[layer.colorID].append(layer)
    	else:
    		if colr.table.LayerRecordArray:
    			for layer in colr.table.LayerRecordArray.LayerRecord:
    				colors_by_index[layer.PaletteIndex].append(layer)
    		for record in colr.table.BaseGlyphList.BaseGlyphPaintRecord:
    			record.Paint.traverse(colr.table, collect_colors_by_index)

    	# don't remap palette entry index 0xFFFF, this is always the foreground color
    	# https://github.com/fonttools/fonttools/issues/2257
    	retained_palette_indices = set(colors_by_index.keys()) - {0xFFFF}
    	for palette in self.palettes:
    		palette[:] = [c for i, c in enumerate(palette) if i in retained_palette_indices]
    		assert len(palette) == len(retained_palette_indices)

    	for new_index, old_index in enumerate(sorted(retained_palette_indices)):
    		for record in colors_by_index[old_index]:
    			if hasattr(record, "colorID"):  # v0
    				record.colorID = new_index
    			elif hasattr(record, "PaletteIndex"):  # v1
    				record.PaletteIndex = new_index
    			else:
    				raise AssertionError(record)

    	self.numPaletteEntries = len(self.palettes[0])

    	if self.version == 1:
    		kept_labels = []
    		dropped_labels = []
    		for i, label in enumerate(self.paletteEntryLabels):
    			if i in retained_palette_indices:
    				kept_labels.append(label)
    			else:
    				dropped_labels.append(label)
    		self.paletteEntryLabels = kept_labels
    		# Remove dropped labels from the name table.
    		name_table = font["name"]
    		name_table.names = [
    			n for n in name_table.names
    			if (
    				n.nameID not in dropped_labels
    				# Only remove nameIDs in the user range and if they're not explicitly kept
    				or n.nameID < 256
    				or n.nameID in options.name_IDs
    			)
    		]
    	return bool(self.numPaletteEntries)

    @_add_method(otTables.MathGlyphConstruction)
    def closure_glyphs(self, glyphs):
    	variants = set()
    	for v in self.MathGlyphVariantRecord:
    		variants.add(v.VariantGlyph)
    	if self.GlyphAssembly:
    		for p in self.GlyphAssembly.PartRecords:
    			variants.add(p.glyph)
    	return variants

    @_add_method(otTables.MathVariants)
    def closure_glyphs(self, s):
    	glyphs = frozenset(s.glyphs)
    	variants = set()

    	if self.VertGlyphCoverage:
    		indices = self.VertGlyphCoverage.intersect(glyphs)
    		for i in indices:
    			variants.update(self.VertGlyphConstruction[i].closure_glyphs(glyphs))

    	if self.HorizGlyphCoverage:
    		indices = self.HorizGlyphCoverage.intersect(glyphs)
    		for i in indices:
    			variants.update(self.HorizGlyphConstruction[i].closure_glyphs(glyphs))

    	s.glyphs.update(variants)

    @_add_method(ttLib.getTableClass('MATH'))
    def closure_glyphs(self, s):
    	if self.table.MathVariants:
    		self.table.MathVariants.closure_glyphs(s)

    @_add_method(otTables.MathItalicsCorrectionInfo)
    def subset_glyphs(self, s):
    	indices = self.Coverage.subset(s.glyphs)
    	self.ItalicsCorrection = _list_subset(self.ItalicsCorrection, indices)
    	self.ItalicsCorrectionCount = len(self.ItalicsCorrection)
    	return bool(self.ItalicsCorrectionCount)

    @_add_method(otTables.MathTopAccentAttachment)
    def subset_glyphs(self, s):
    	indices = self.TopAccentCoverage.subset(s.glyphs)
    	self.TopAccentAttachment = _list_subset(self.TopAccentAttachment, indices)
    	self.TopAccentAttachmentCount = len(self.TopAccentAttachment)
    	return bool(self.TopAccentAttachmentCount)

    @_add_method(otTables.MathKernInfo)
    def subset_glyphs(self, s):
    	indices = self.MathKernCoverage.subset(s.glyphs)
    	self.MathKernInfoRecords = _list_subset(self.MathKernInfoRecords, indices)
    	self.MathKernCount = len(self.MathKernInfoRecords)
    	return bool(self.MathKernCount)

    @_add_method(otTables.MathGlyphInfo)
    def subset_glyphs(self, s):
    	if self.MathItalicsCorrectionInfo:
    		self.MathItalicsCorrectionInfo.subset_glyphs(s)
    	if self.MathTopAccentAttachment:
    		self.MathTopAccentAttachment.subset_glyphs(s)
    	if self.MathKernInfo:
    		self.MathKernInfo.subset_glyphs(s)
    	if self.ExtendedShapeCoverage:
    		self.ExtendedShapeCoverage.subset(s.glyphs)
    	return True

    @_add_method(otTables.MathVariants)
    def subset_glyphs(self, s):
    	if self.VertGlyphCoverage:
    		indices = self.VertGlyphCoverage.subset(s.glyphs)
    		self.VertGlyphConstruction = _list_subset(self.VertGlyphConstruction, indices)
    		self.VertGlyphCount = len(self.VertGlyphConstruction)

    	if self.HorizGlyphCoverage:
    		indices = self.HorizGlyphCoverage.subset(s.glyphs)
    		self.HorizGlyphConstruction = _list_subset(self.HorizGlyphConstruction, indices)
    		self.HorizGlyphCount = len(self.HorizGlyphConstruction)

    	return True

    @_add_method(ttLib.getTableClass('MATH'))
    def subset_glyphs(self, s):
    	s.glyphs = s.glyphs_mathed
    	if self.table.MathGlyphInfo:
    		self.table.MathGlyphInfo.subset_glyphs(s)
    	if self.table.MathVariants:
    		self.table.MathVariants.subset_glyphs(s)
    	return True

    @_add_method(ttLib.getTableModule('glyf').Glyph)
    def remapComponentsFast(self, glyphidmap):
    	if not self.data or struct.unpack(">h", self.data[:2])[0] >= 0:
    		return	# Not composite
    	data = self.data = bytearray(self.data)
    	i = 10
    	more = 1
    	while more:
    		flags =(data[i] << 8) | data[i+1]
    		glyphID =(data[i+2] << 8) | data[i+3]
    		# Remap
    		glyphID = glyphidmap[glyphID]
    		data[i+2] = glyphID >> 8
    		data[i+3] = glyphID & 0xFF
    		i += 4
    		flags = int(flags)

    		if flags & 0x0001: i += 4	# ARG_1_AND_2_ARE_WORDS
    		else: i += 2
    		if flags & 0x0008: i += 2	# WE_HAVE_A_SCALE
    		elif flags & 0x0040: i += 4	# WE_HAVE_AN_X_AND_Y_SCALE
    		elif flags & 0x0080: i += 8	# WE_HAVE_A_TWO_BY_TWO
    		more = flags & 0x0020	# MORE_COMPONENTS

    @_add_method(ttLib.getTableClass('glyf'))
    def closure_glyphs(self, s):
    	glyphSet = self.glyphs
    	decompose = s.glyphs
    	while decompose:
    		components = set()
    		for g in decompose:
    			if g not in glyphSet:
    				continue
    			gl = glyphSet[g]
    			for c in gl.getComponentNames(self):
    				components.add(c)
    		components -= s.glyphs
    		s.glyphs.update(components)
    		decompose = components

    @_add_method(ttLib.getTableClass('glyf'))
    def prune_pre_subset(self, font, options):
    	if options.notdef_glyph and not options.notdef_outline:
    		g = self[self.glyphOrder[0]]
    		# Yay, easy!
    		g.__dict__.clear()
    		g.data = b''
    	return True

    @_add_method(ttLib.getTableClass('glyf'))
    def subset_glyphs(self, s):
    	self.glyphs = _dict_subset(self.glyphs, s.glyphs)
    	if not s.options.retain_gids:
    		indices = [i for i,g in enumerate(self.glyphOrder) if g in s.glyphs]
    		glyphmap = {o:n for n,o in enumerate(indices)}
    		for v in self.glyphs.values():
    			if hasattr(v, "data"):
    				v.remapComponentsFast(glyphmap)
    	Glyph = ttLib.getTableModule('glyf').Glyph
    	for g in s.glyphs_emptied:
    		self.glyphs[g] = Glyph()
    		self.glyphs[g].data = b''
    	self.glyphOrder = [g for g in self.glyphOrder if g in s.glyphs or g in s.glyphs_emptied]
    	# Don't drop empty 'glyf' tables, otherwise 'loca' doesn't get subset.
    	return True

    @_add_method(ttLib.getTableClass('glyf'))
    def prune_post_subset(self, font, options):
    	remove_hinting = not options.hinting
    	for v in self.glyphs.values():
    		v.trim(remove_hinting=remove_hinting)
    	return True

    @_add_method(ttLib.getTableClass('cmap'))
    def closure_glyphs(self, s):
    	tables = [t for t in self.tables if t.isUnicode()]

    	# Close glyphs
    	for table in tables:
    		if table.format == 14:
    			for cmap in table.uvsDict.values():
    				glyphs = {g for u,g in cmap if u in s.unicodes_requested}
    				if None in glyphs:
    					glyphs.remove(None)
    				s.glyphs.update(glyphs)
    		else:
    			cmap = table.cmap
    			intersection = s.unicodes_requested.intersection(cmap.keys())
    			s.glyphs.update(cmap[u] for u in intersection)

    	# Calculate unicodes_missing
    	s.unicodes_missing = s.unicodes_requested.copy()
    	for table in tables:
    		s.unicodes_missing.difference_update(table.cmap)

    @_add_method(ttLib.getTableClass('cmap'))
    def prune_pre_subset(self, font, options):
    	if not options.legacy_cmap:
    		# Drop non-Unicode / non-Symbol cmaps
    		self.tables = [t for t in self.tables if t.isUnicode() or t.isSymbol()]
    	if not options.symbol_cmap:
    		self.tables = [t for t in self.tables if not t.isSymbol()]
    	# TODO(behdad) Only keep one subtable?
    	# For now, drop format=0 which can't be subset_glyphs easily?
    	self.tables = [t for t in self.tables if t.format != 0]
    	self.numSubTables = len(self.tables)
    	return True # Required table

    @_add_method(ttLib.getTableClass('cmap'))
    def subset_glyphs(self, s):
    	s.glyphs = None # We use s.glyphs_requested and s.unicodes_requested only

    	tables_format12_bmp = []
    	table_plat0_enc3 = {}  # Unicode platform, Unicode BMP only, keyed by language
    	table_plat3_enc1 = {}  # Windows platform, Unicode BMP, keyed by language

    	for t in self.tables:
    		if t.platformID == 0 and t.platEncID == 3:
    			table_plat0_enc3[t.language] = t
    		if t.platformID == 3 and t.platEncID == 1:
    			table_plat3_enc1[t.language] = t

    		if t.format == 14:
    			# TODO(behdad) We drop all the default-UVS mappings
    			# for glyphs_requested.  So it's the caller's responsibility to make
    			# sure those are included.
    			t.uvsDict = {v:[(u,g) for u,g in l
    					      if g in s.glyphs_requested or u in s.unicodes_requested]
    				     for v,l in t.uvsDict.items()}
    			t.uvsDict = {v:l for v,l in t.uvsDict.items() if l}
    		elif t.isUnicode():
    			t.cmap = {u:g for u,g in t.cmap.items()
    				      if g in s.glyphs_requested or u in s.unicodes_requested}
    			# Collect format 12 tables that hold only basic multilingual plane
    			# codepoints.
    			if t.format == 12 and t.cmap and max(t.cmap.keys()) < 0x10000:
    				tables_format12_bmp.append(t)
    		else:
    			t.cmap = {u:g for u,g in t.cmap.items()
    				      if g in s.glyphs_requested}

    	# Fomat 12 tables are redundant if they contain just the same BMP codepoints
    	# their little BMP-only encoding siblings contain.
    	for t in tables_format12_bmp:
    		if (
    			t.platformID == 0  # Unicode platform
    			and t.platEncID == 4  # Unicode full repertoire
    			and t.language in table_plat0_enc3  # Have a BMP-only sibling?
    			and table_plat0_enc3[t.language].cmap == t.cmap
    		):
    			t.cmap.clear()
    		elif (
    			t.platformID == 3  # Windows platform
    			and t.platEncID == 10  # Unicode full repertoire
    			and t.language in table_plat3_enc1  # Have a BMP-only sibling?
    			and table_plat3_enc1[t.language].cmap == t.cmap
    		):
    			t.cmap.clear()

    	self.tables = [t for t in self.tables
    			 if (t.cmap if t.format != 14 else t.uvsDict)]
    	self.numSubTables = len(self.tables)
    	# TODO(behdad) Convert formats when needed.
    	# In particular, if we have a format=12 without non-BMP
    	# characters, convert it to format=4 if there's not one.
    	return True # Required table

    @_add_method(ttLib.getTableClass('DSIG'))
    def prune_pre_subset(self, font, options):
    	# Drop all signatures since they will be invalid
    	self.usNumSigs = 0
    	self.signatureRecords = []
    	return True

    @_add_method(ttLib.getTableClass('maxp'))
    def prune_pre_subset(self, font, options):
    	if not options.hinting:
    		if self.tableVersion == 0x00010000:
    			self.maxZones = 1
    			self.maxTwilightPoints = 0
    			self.maxStorage = 0
    			self.maxFunctionDefs = 0
    			self.maxInstructionDefs = 0
    			self.maxStackElements = 0
    			self.maxSizeOfInstructions = 0
    	return True

    @_add_method(ttLib.getTableClass('name'))
    def prune_pre_subset(self, font, options):
    	nameIDs = set(options.name_IDs)
    	fvar = font.get('fvar')
    	if fvar:
    		nameIDs.update([axis.axisNameID for axis in fvar.axes])
    		nameIDs.update([inst.subfamilyNameID for inst in fvar.instances])
    		nameIDs.update([inst.postscriptNameID for inst in fvar.instances
    				if inst.postscriptNameID != 0xFFFF])
    	stat = font.get('STAT')
    	if stat:
    		if stat.table.AxisValueArray:
    			nameIDs.update([val_rec.ValueNameID for val_rec in stat.table.AxisValueArray.AxisValue])
    		nameIDs.update([axis_rec.AxisNameID for axis_rec in stat.table.DesignAxisRecord.Axis])
    	cpal = font.get('CPAL')
    	if cpal and cpal.version == 1:
    		nameIDs.update(cpal.paletteLabels)
    		nameIDs.update(cpal.paletteEntryLabels)
    	if '*' not in options.name_IDs:
    		self.names = [n for n in self.names if n.nameID in nameIDs]
    	if not options.name_legacy:
    		# TODO(behdad) Sometimes (eg Apple Color Emoji) there's only a macroman
    		# entry for Latin and no Unicode names.
    		self.names = [n for n in self.names if n.isUnicode()]
    	# TODO(behdad) Option to keep only one platform's
    	if '*' not in options.name_languages:
    		# TODO(behdad) This is Windows-platform specific!
    		self.names = [n for n in self.names
    				if n.langID in options.name_languages]
    	if options.obfuscate_names:
    		namerecs = []
    		for n in self.names:
    			if n.nameID in [1, 4]:
    				n.string = ".\x7f".encode('utf_16_be') if n.isUnicode() else ".\x7f"
    			elif n.nameID in [2, 6]:
    				n.string = "\x7f".encode('utf_16_be') if n.isUnicode() else "\x7f"
    			elif n.nameID == 3:
    				n.string = ""
    			elif n.nameID in [16, 17, 18]:
    				continue
    			namerecs.append(n)
    		self.names = namerecs
    	return True	# Required table

    @_add_method(ttLib.getTableClass('head'))
    def prune_post_subset(self, font, options):
    	# Force re-compiling head table, to update any recalculated values.
    	return True

    # TODO(behdad) OS/2 ulCodePageRange?
    # TODO(behdad) Drop AAT tables.
    # TODO(behdad) Drop unneeded GSUB/GPOS Script/LangSys entries.
    # TODO(behdad) Drop empty GSUB/GPOS, and GDEF if no GSUB/GPOS left
    # TODO(behdad) Drop GDEF subitems if unused by lookups
    # TODO(behdad) Avoid recursing too much (in GSUB/GPOS and in CFF)
    # TODO(behdad) Text direction considerations.
    # TODO(behdad) Text script / language considerations.
    # TODO(behdad) Optionally drop 'kern' table if GPOS available
    # TODO(behdad) Implement --unicode='*' to choose all cmap'ed
    # TODO(behdad) Drop old-spec Indic scripts

    class Options(object):

    	class OptionError(Exception): pass
    	class UnknownOptionError(OptionError): pass

    	# spaces in tag names (e.g. "SVG ", "cvt ") are stripped by the argument parser
    	_drop_tables_default = ['BASE', 'JSTF', 'DSIG', 'EBDT', 'EBLC',
    				'EBSC', 'PCLT', 'LTSH']
    	_drop_tables_default += ['Feat', 'Glat', 'Gloc', 'Silf', 'Sill']  # Graphite
    	_no_subset_tables_default = ['avar', 'fvar',
    				     'gasp', 'head', 'hhea', 'maxp',
    				     'vhea', 'OS/2', 'loca', 'name', 'cvt',
    				     'fpgm', 'prep', 'VDMX', 'DSIG', 'CPAL',
    				     'MVAR', 'cvar', 'STAT']
    	_hinting_tables_default = ['cvt', 'cvar', 'fpgm', 'prep', 'hdmx', 'VDMX']

    	# Based on HarfBuzz shapers
    	_layout_features_groups = {
    		# Default shaper
    		'common': ['rvrn', 'ccmp', 'liga', 'locl', 'mark', 'mkmk', 'rlig'],
    		'fractions': ['frac', 'numr', 'dnom'],
    		'horizontal': ['calt', 'clig', 'curs', 'kern', 'rclt'],
    		'vertical': ['valt', 'vert', 'vkrn', 'vpal', 'vrt2'],
    		'ltr': ['ltra', 'ltrm'],
    		'rtl': ['rtla', 'rtlm'],
    		'rand': ['rand'],
    		'justify': ['jalt'],
    		'private': ['Harf', 'HARF', 'Buzz', 'BUZZ'],
    		# Complex shapers
    		'arabic': ['init', 'medi', 'fina', 'isol', 'med2', 'fin2', 'fin3',
    			   'cswh', 'mset', 'stch'],
    		'hangul': ['ljmo', 'vjmo', 'tjmo'],
    		'tibetan': ['abvs', 'blws', 'abvm', 'blwm'],
    		'indic': ['nukt', 'akhn', 'rphf', 'rkrf', 'pref', 'blwf', 'half',
    			  'abvf', 'pstf', 'cfar', 'vatu', 'cjct', 'init', 'pres',
    			  'abvs', 'blws', 'psts', 'haln', 'dist', 'abvm', 'blwm'],
    	}
    	_layout_features_default = _uniq_sort(sum(
    			iter(_layout_features_groups.values()), []))

    	def __init__(self, **kwargs):

    		self.drop_tables = self._drop_tables_default[:]
    		self.no_subset_tables = self._no_subset_tables_default[:]
    		self.passthrough_tables = False  # keep/drop tables we can't subset
    		self.hinting_tables = self._hinting_tables_default[:]
    		self.legacy_kern = False # drop 'kern' table if GPOS available
    		self.layout_closure = True
    		self.layout_features = self._layout_features_default[:]
    		self.layout_scripts = ['*']
    		self.ignore_missing_glyphs = False
    		self.ignore_missing_unicodes = True
    		self.hinting = True
    		self.glyph_names = False
    		self.legacy_cmap = False
    		self.symbol_cmap = False
    		self.name_IDs = [0, 1, 2, 3, 4, 5, 6] # https://github.com/fonttools/fonttools/issues/1170#issuecomment-364631225
    		self.name_legacy = False
    		self.name_languages = [0x0409] # English
    		self.obfuscate_names = False # to make webfont unusable as a system font
    		self.retain_gids = False
    		self.notdef_glyph = True # gid0 for TrueType / .notdef for CFF
    		self.notdef_outline = False # No need for notdef to have an outline really
    		self.recommended_glyphs = False # gid1, gid2, gid3 for TrueType
    		self.recalc_bounds = False # Recalculate font bounding boxes
    		self.recalc_timestamp = False # Recalculate font modified timestamp
    		self.prune_unicode_ranges = True # Clear unused 'ulUnicodeRange' bits
    		self.recalc_average_width = False # update 'xAvgCharWidth'
    		self.recalc_max_context = False # update 'usMaxContext'
    		self.canonical_order = None # Order tables as recommended
    		self.flavor = None  # May be 'woff' or 'woff2'
    		self.with_zopfli = False  # use zopfli instead of zlib for WOFF 1.0
    		self.desubroutinize = False # Desubroutinize CFF CharStrings
    		self.harfbuzz_repacker = USE_HARFBUZZ_REPACKER.default
    		self.verbose = False
    		self.timing = False
    		self.xml = False
    		self.font_number = -1
    		self.pretty_svg = False
    		self.lazy = True

    		self.set(**kwargs)

    	def set(self, **kwargs):
    		for k,v in kwargs.items():
    			if not hasattr(self, k):
    				raise self.UnknownOptionError("Unknown option '%s'" % k)
    			setattr(self, k, v)

    	def parse_opts(self, argv, ignore_unknown=[]):
    		posargs = []
    		passthru_options = []
    		for a in argv:
    			orig_a = a
    			if not a.startswith('--'):
    				posargs.append(a)
    				continue
    			a = a[2:]
    			i = a.find('=')
    			op = '='
    			if i == -1:
    				if a.startswith("no-"):
    					k = a[3:]
    					if k == "canonical-order":
    						# reorderTables=None is faster than False (the latter
    						# still reorders to "keep" the original table order)
    						v = None
    					else:
    						v = False
    				else:
    					k = a
    					v = True
    				if k.endswith("?"):
    					k = k[:-1]
    					v = '?'
    			else:
    				k = a[:i]
    				if k[-1] in "-+":
    					op = k[-1]+'='	# Op is '-=' or '+=' now.
    					k = k[:-1]
    				v = a[i+1:]
    			ok = k
    			k = k.replace('-', '_')
    			if not hasattr(self, k):
    				if ignore_unknown is True or ok in ignore_unknown:
    					passthru_options.append(orig_a)
    					continue
    				else:
    					raise self.UnknownOptionError("Unknown option '%s'" % a)

    			ov = getattr(self, k)
    			if v == '?':
    					print("Current setting for '%s' is: %s" % (ok, ov))
    					continue
    			if isinstance(ov, bool):
    				v = bool(v)
    			elif isinstance(ov, int):
    				v = int(v)
    			elif isinstance(ov, str):
    				v = str(v) # redundant
    			elif isinstance(ov, list):
    				if isinstance(v, bool):
    					raise self.OptionError("Option '%s' requires values to be specified using '='" % a)
    				vv = v.replace(',', ' ').split()
    				if vv == ['']:
    					vv = []
    				vv = [int(x, 0) if len(x) and x[0] in "0123456789" else x for x in vv]
    				if op == '=':
    					v = vv
    				elif op == '+=':
    					v = ov
    					v.extend(vv)
    				elif op == '-=':
    					v = ov
    					for x in vv:
    						if x in v:
    							v.remove(x)
    				else:
    					assert False

    			setattr(self, k, v)

    		return posargs + passthru_options

    class Subsetter(object):

    	class SubsettingError(Exception): pass
    	class MissingGlyphsSubsettingError(SubsettingError): pass
    	class MissingUnicodesSubsettingError(SubsettingError): pass

    	def __init__(self, options=None):

    		if not options:
    			options = Options()

    		self.options = options
    		self.unicodes_requested = set()
    		self.glyph_names_requested = set()
    		self.glyph_ids_requested = set()

    	def populate(self, glyphs=[], gids=[], unicodes=[], text=""):
    		self.unicodes_requested.update(unicodes)
    		if isinstance(text, bytes):
    			text = text.decode("utf_8")
    		text_utf32 = text.encode("utf-32-be")
    		nchars = len(text_utf32)//4
    		for u in struct.unpack('>%dL' % nchars, text_utf32):
    			self.unicodes_requested.add(u)
    		self.glyph_names_requested.update(glyphs)
    		self.glyph_ids_requested.update(gids)

    	def _prune_pre_subset(self, font):
    		for tag in self._sort_tables(font):
    			if (tag.strip() in self.options.drop_tables or
    			    (tag.strip() in self.options.hinting_tables and not self.options.hinting) or
    			    (tag == 'kern' and (not self.options.legacy_kern and 'GPOS' in font))):
    				log.info("%s dropped", tag)
    				del font[tag]
    				continue

    			clazz = ttLib.getTableClass(tag)

    			if hasattr(clazz, 'prune_pre_subset'):
    				with timer("load '%s'" % tag):
    					table = font[tag]
    				with timer("prune '%s'" % tag):
    					retain = table.prune_pre_subset(font, self.options)
    				if not retain:
    					log.info("%s pruned to empty; dropped", tag)
    					del font[tag]
    					continue
    				else:
    					log.info("%s pruned", tag)

    	def _closure_glyphs(self, font):

    		realGlyphs = set(font.getGlyphOrder())
    		self.orig_glyph_order = glyph_order = font.getGlyphOrder()

    		self.glyphs_requested = set()
    		self.glyphs_requested.update(self.glyph_names_requested)
    		self.glyphs_requested.update(glyph_order[i]
    					     for i in self.glyph_ids_requested
    					     if i < len(glyph_order))

    		self.glyphs_missing = set()
    		self.glyphs_missing.update(self.glyphs_requested.difference(realGlyphs))
    		self.glyphs_missing.update(i for i in self.glyph_ids_requested
    					     if i >= len(glyph_order))
    		if self.glyphs_missing:
    			log.info("Missing requested glyphs: %s", self.glyphs_missing)
    			if not self.options.ignore_missing_glyphs:
    				raise self.MissingGlyphsSubsettingError(self.glyphs_missing)

    		self.glyphs = self.glyphs_requested.copy()

    		self.unicodes_missing = set()
    		if 'cmap' in font:
    			with timer("close glyph list over 'cmap'"):
    				font['cmap'].closure_glyphs(self)
    				self.glyphs.intersection_update(realGlyphs)
    		self.glyphs_cmaped = frozenset(self.glyphs)
    		if self.unicodes_missing:
    			missing = ["U+%04X" % u for u in self.unicodes_missing]
    			log.info("Missing glyphs for requested Unicodes: %s", missing)
    			if not self.options.ignore_missing_unicodes:
    				raise self.MissingUnicodesSubsettingError(missing)
    			del missing

    		if self.options.notdef_glyph:
    			if 'glyf' in font:
    				self.glyphs.add(font.getGlyphName(0))
    				log.info("Added gid0 to subset")
    			else:
    				self.glyphs.add('.notdef')
    				log.info("Added .notdef to subset")
    		if self.options.recommended_glyphs:
    			if 'glyf' in font:
    				for i in range(min(4, len(font.getGlyphOrder()))):
    					self.glyphs.add(font.getGlyphName(i))
    				log.info("Added first four glyphs to subset")

    		if self.options.layout_closure and 'GSUB' in font:
    			with timer("close glyph list over 'GSUB'"):
    				log.info("Closing glyph list over 'GSUB': %d glyphs before",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    				font['GSUB'].closure_glyphs(self)
    				self.glyphs.intersection_update(realGlyphs)
    				log.info("Closed glyph list over 'GSUB': %d glyphs after",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    		self.glyphs_gsubed = frozenset(self.glyphs)

    		if 'MATH' in font:
    			with timer("close glyph list over 'MATH'"):
    				log.info("Closing glyph list over 'MATH': %d glyphs before",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    				font['MATH'].closure_glyphs(self)
    				self.glyphs.intersection_update(realGlyphs)
    				log.info("Closed glyph list over 'MATH': %d glyphs after",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    		self.glyphs_mathed = frozenset(self.glyphs)

    		for table in ('COLR', 'bsln'):
    			if table in font:
    				with timer("close glyph list over '%s'" % table):
    					log.info("Closing glyph list over '%s': %d glyphs before",
    							 table, len(self.glyphs))
    					log.glyphs(self.glyphs, font=font)
    					font[table].closure_glyphs(self)
    					self.glyphs.intersection_update(realGlyphs)
    					log.info("Closed glyph list over '%s': %d glyphs after",
    							 table, len(self.glyphs))
    					log.glyphs(self.glyphs, font=font)
    			setattr(self, f"glyphs_{table.lower()}ed", frozenset(self.glyphs))

    		if 'glyf' in font:
    			with timer("close glyph list over 'glyf'"):
    				log.info("Closing glyph list over 'glyf': %d glyphs before",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    				font['glyf'].closure_glyphs(self)
    				self.glyphs.intersection_update(realGlyphs)
    				log.info("Closed glyph list over 'glyf': %d glyphs after",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    		self.glyphs_glyfed = frozenset(self.glyphs)

    		if 'CFF ' in font:
    			with timer("close glyph list over 'CFF '"):
    				log.info("Closing glyph list over 'CFF ': %d glyphs before",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    				font['CFF '].closure_glyphs(self)
    				self.glyphs.intersection_update(realGlyphs)
    				log.info("Closed glyph list over 'CFF ': %d glyphs after",
    						 len(self.glyphs))
    				log.glyphs(self.glyphs, font=font)
    		self.glyphs_cffed = frozenset(self.glyphs)

    		self.glyphs_retained = frozenset(self.glyphs)

    		order = font.getReverseGlyphMap()
    		self.reverseOrigGlyphMap = {g:order[g] for g in self.glyphs_retained}

    		self.last_retained_order = max(self.reverseOrigGlyphMap.values())
    		self.last_retained_glyph = font.getGlyphOrder()[self.last_retained_order]

    		self.glyphs_emptied = frozenset()
    		if self.options.retain_gids:
    			self.glyphs_emptied = {g for g in realGlyphs - self.glyphs_retained if order[g] <= self.last_retained_order}

    		self.reverseEmptiedGlyphMap = {g:order[g] for g in self.glyphs_emptied}

    		if not self.options.retain_gids:
    			new_glyph_order = [
    				g for g in glyph_order if g in self.glyphs_retained
    			]
    		else:
    			new_glyph_order = [
    				g for g in glyph_order
    				if font.getGlyphID(g) <= self.last_retained_order
    			]
    		# We'll call font.setGlyphOrder() at the end of _subset_glyphs when all
    		# tables have been subsetted. Below, we use the new glyph order to get
    		# a map from old to new glyph indices, which can be useful when
    		# subsetting individual tables (e.g. SVG) that refer to GIDs.
    		self.new_glyph_order = new_glyph_order
    		self.glyph_index_map = {
    			order[new_glyph_order[i]]: i
    			for i in range(len(new_glyph_order))
    		}

    		log.info("Retaining %d glyphs", len(self.glyphs_retained))

    		del self.glyphs

    	def _subset_glyphs(self, font):
    		for tag in self._sort_tables(font):
    			clazz = ttLib.getTableClass(tag)

    			if tag.strip() in self.options.no_subset_tables:
    				log.info("%s subsetting not needed", tag)
    			elif hasattr(clazz, 'subset_glyphs'):
    				with timer("subset '%s'" % tag):
    					table = font[tag]
    					self.glyphs = self.glyphs_retained
    					retain = table.subset_glyphs(self)
    					del self.glyphs
    				if not retain:
    					log.info("%s subsetted to empty; dropped", tag)
    					del font[tag]
    				else:
    					log.info("%s subsetted", tag)
    			elif self.options.passthrough_tables:
    				log.info("%s NOT subset; don't know how to subset", tag)
    			else:
    				log.warning("%s NOT subset; don't know how to subset; dropped", tag)
    				del font[tag]

    		with timer("subset GlyphOrder"):
    			font.setGlyphOrder(self.new_glyph_order)

    	def _prune_post_subset(self, font):
    		for tag in font.keys():
    			if tag == 'GlyphOrder': continue
    			if tag == 'OS/2' and self.options.prune_unicode_ranges:
    				old_uniranges = font[tag].getUnicodeRanges()
    				new_uniranges = font[tag].recalcUnicodeRanges(font, pruneOnly=True)
    				if old_uniranges != new_uniranges:
    					log.info("%s Unicode ranges pruned: %s", tag, sorted(new_uniranges))
    				if self.options.recalc_average_width:
    					old_avg_width = font[tag].xAvgCharWidth
    					new_avg_width = font[tag].recalcAvgCharWidth(font)
    					if old_avg_width != new_avg_width:
    						log.info("%s xAvgCharWidth updated: %d", tag, new_avg_width)
    				if self.options.recalc_max_context:
    					max_context = maxCtxFont(font)
    					if max_context != font[tag].usMaxContext:
    						font[tag].usMaxContext = max_context
    						log.info("%s usMaxContext updated: %d", tag, max_context)
    			clazz = ttLib.getTableClass(tag)
    			if hasattr(clazz, 'prune_post_subset'):
    				with timer("prune '%s'" % tag):
    					table = font[tag]
    					retain = table.prune_post_subset(font, self.options)
    				if not retain:
    					log.info("%s pruned to empty; dropped", tag)
    					del font[tag]
    				else:
    					log.info("%s pruned", tag)

    	def _sort_tables(self, font):
    		tagOrder = ['fvar', 'avar', 'gvar', 'name', 'glyf']
    		tagOrder = {t: i + 1 for i, t in enumerate(tagOrder)}
    		tags = sorted(font.keys(), key=lambda tag: tagOrder.get(tag, 0))
    		return [t for t in tags if t != 'GlyphOrder']

    	def subset(self, font):
    		self._prune_pre_subset(font)
    		self._closure_glyphs(font)
    		self._subset_glyphs(font)
    		self._prune_post_subset(font)

    @timer("load font")
    def load_font(fontFile,
    	      options,
    	      checkChecksums=0,
    	      dontLoadGlyphNames=False,
    	      lazy=True):

    	font = ttLib.TTFont(fontFile,
    			    checkChecksums=checkChecksums,
    			    recalcBBoxes=options.recalc_bounds,
    			    recalcTimestamp=options.recalc_timestamp,
    			    lazy=lazy,
    			    fontNumber=options.font_number)

    	# Hack:
    	#
    	# If we don't need glyph names, change 'post' class to not try to
    	# load them.	It avoid lots of headache with broken fonts as well
    	# as loading time.
    	#
    	# Ideally ttLib should provide a way to ask it to skip loading
    	# glyph names.	But it currently doesn't provide such a thing.
    	#
    	if dontLoadGlyphNames:
    		post = ttLib.getTableClass('post')
    		saved = post.decode_format_2_0
    		post.decode_format_2_0 = post.decode_format_3_0
    		f = font['post']
    		if f.formatType == 2.0:
    			f.formatType = 3.0
    		post.decode_format_2_0 = saved

    	return font

    @timer("compile and save font")
    def save_font(font, outfile, options):
    	if options.with_zopfli and options.flavor == "woff":
    		from fontTools.ttLib import sfnt
    		sfnt.USE_ZOPFLI = True
    	font.flavor = options.flavor
    	font.cfg[USE_HARFBUZZ_REPACKER] = options.harfbuzz_repacker
    	font.save(outfile, reorderTables=options.canonical_order)

    def parse_unicodes(s):
    	import re
    	s = re.sub (r"0[xX]", " ", s)
    	s = re.sub (r"[<+>,;&#\\xXuU\n	]", " ", s)
    	l = []
    	for item in s.split():
    		fields = item.split('-')
    		if len(fields) == 1:
    			l.append(int(item, 16))
    		else:
    			start,end = fields
    			l.extend(range(int(start, 16), int(end, 16)+1))
    	return l

    def parse_gids(s):
    	l = []
    	for item in s.replace(',', ' ').split():
    		fields = item.split('-')
    		if len(fields) == 1:
    			l.append(int(fields[0]))
    		else:
    			l.extend(range(int(fields[0]), int(fields[1])+1))
    	return l

    def parse_glyphs(s):
    	return s.replace(',', ' ').split()

    def usage():
    	print("usage:", __usage__, file=sys.stderr)
    	print("Try pyftsubset --help for more information.\n", file=sys.stderr)

    @timer("make one with everything (TOTAL TIME)")
    def main(args=None):
    	"""OpenType font subsetter and optimizer"""
    	from os.path import splitext
    	from fontTools import configLogger

    	if args is None:
    		args = sys.argv[1:]

    	if '--help' in args:
    		print(__doc__)
    		return 0

    	options = Options()
    	try:
    		args = options.parse_opts(args,
    			ignore_unknown=['gids', 'gids-file',
    							'glyphs', 'glyphs-file',
    							'text', 'text-file',
    							'unicodes', 'unicodes-file',
    							'output-file'])
    	except options.OptionError as e:
    		usage()
    		print("ERROR:", e, file=sys.stderr)
    		return 2

    	if len(args) < 2:
    		usage()
    		return 1

    	configLogger(level=logging.INFO if options.verbose else logging.WARNING)
    	if options.timing:
    		timer.logger.setLevel(logging.DEBUG)
    	else:
    		timer.logger.disabled = True

    	fontfile = args[0]
    	args = args[1:]

    	subsetter = Subsetter(options=options)
    	outfile = None
    	glyphs = []
    	gids = []
    	unicodes = []
    	wildcard_glyphs = False
    	wildcard_unicodes = False
    	text = ""
    	for g in args:
    		if g == '*':
    			wildcard_glyphs = True
    			continue
    		if g.startswith('--output-file='):
    			outfile = g[14:]
    			continue
    		if g.startswith('--text='):
    			text += g[7:]
    			continue
    		if g.startswith('--text-file='):
    			with open(g[12:], encoding='utf-8') as f:
    				text += f.read().replace('\n', '')
    			continue
    		if g.startswith('--unicodes='):
    			if g[11:] == '*':
    				wildcard_unicodes = True
    			else:
    				unicodes.extend(parse_unicodes(g[11:]))
    			continue
    		if g.startswith('--unicodes-file='):
    			with open(g[16:]) as f:
    				for line in f.readlines():
    					unicodes.extend(parse_unicodes(line.split('#')[0]))
    			continue
    		if g.startswith('--gids='):
    			gids.extend(parse_gids(g[7:]))
    			continue
    		if g.startswith('--gids-file='):
    			with open(g[12:]) as f:
    				for line in f.readlines():
    					gids.extend(parse_gids(line.split('#')[0]))
    			continue
    		if g.startswith('--glyphs='):
    			if g[9:] == '*':
    				wildcard_glyphs = True
    			else:
    				glyphs.extend(parse_glyphs(g[9:]))
    			continue
    		if g.startswith('--glyphs-file='):
    			with open(g[14:]) as f:
    				for line in f.readlines():
    					glyphs.extend(parse_glyphs(line.split('#')[0]))
    			continue
    		glyphs.append(g)

    	dontLoadGlyphNames = not options.glyph_names and not glyphs
    	lazy = options.lazy
    	font = load_font(fontfile, options, dontLoadGlyphNames=dontLoadGlyphNames, lazy=lazy)

    	if outfile is None:
    		outfile = makeOutputFileName(fontfile, overWrite=True, suffix=".subset")

    	with timer("compile glyph list"):
    		if wildcard_glyphs:
    			glyphs.extend(font.getGlyphOrder())
    		if wildcard_unicodes:
    			for t in font['cmap'].tables:
    				if t.isUnicode():
    					unicodes.extend(t.cmap.keys())
    		assert '' not in glyphs

    	log.info("Text: '%s'" % text)
    	log.info("Unicodes: %s", unicodes)
    	log.info("Glyphs: %s", glyphs)
    	log.info("Gids: %s", gids)

    	subsetter.populate(glyphs=glyphs, gids=gids, unicodes=unicodes, text=text)
    	subsetter.subset(font)

    	save_font(font, outfile, options)

    	if options.verbose:
    		import os
    		log.info("Input font:% 7d bytes: %s" % (os.path.getsize(fontfile), fontfile))
    		log.info("Subset font:% 7d bytes: %s" % (os.path.getsize(outfile), outfile))

    	if options.xml:
    		font.saveXML(sys.stdout)

    	font.close()

    __all__ = [
    	'Options',
    	'Subsetter',
    	'load_font',
    	'save_font',
    	'parse_gids',
    	'parse_glyphs',
    	'parse_unicodes',
    	'main'
    ]

    if __name__ == '__main__':
    	sys.exit(main())