User Guide

FontLab 4
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Glyph classes
A feature file glyph class, <glyphclass>, represents a single glyph position
in a sequence and is denoted by a list of glyphs enclosed in square brackets.
For example:
[endash emdash figuredash]
An example of a sequence that contains a glyph class is:
space [endash emdash figuredash] space
This would match any of the 3 sequences "space endash space", "space
emdash space", or "space figuredash space" during OpenType layout.
A feature file glyph class that contains only one single glyph is known as a
singleton glyph class.
A feature file glyph class is also used to represent the set of alternate glyphs
in an alternate substitution lookup type rule.
Ranges
A range of glyphs is denoted by a hyphen:
[<firstGlyph> - <lastGlyph>]
Spaces around the hyphen are not required since hyphens are not
permitted in feature file glyph names. For example:
[A-Z]