Contextual alternates - switching preceding glyph in calt

Hey —

Is it possible to switch out preceding glyphs in context?

Say I wanted to sub (f, @list) for (f.short, @list).

Trying to avoid making the f.short the default. Otherwise still curious whether it’s possible to switch multiple glyphs at once. ie sub (d o g) by (c a t) without making a c_a_t ligature glyph.

Thought this was possible but can’t find literature.



Of course.

sub f' [context] by f.short;

Thank you — so I take it the ’ signifies what is to be switched. And the jigsaw is complete. Thanks again!
Has a lot of helpful information about substitution and other things.