# OpenType Feature File specification, section 5.d, example 1. # http://www.adobe.com/devnet/opentype/afdko/topic_feature_file_syntax.html feature F1 { sub [one one.oldstyle] [slash fraction] [two two.oldstyle] by onehalf; } F1; # Since the OpenType specification does not allow ligature substitutions # to be specified on target sequences that contain glyph classes, the # implementation software will enumerate all specific glyph sequences # if glyph classes are detected in . Thus, the above # example produces an identical representation in the font as if all # the sequences were manually enumerated by the font editor: feature F2 { sub one slash two by onehalf; sub one.oldstyle slash two by onehalf; sub one fraction two by onehalf; sub one.oldstyle fraction two by onehalf; sub one slash two.oldstyle by onehalf; sub one.oldstyle slash two.oldstyle by onehalf; sub one fraction two.oldstyle by onehalf; sub one.oldstyle fraction two.oldstyle by onehalf; } F2;