Replace glyph by alternate by using the key combination

How to make an automatic replacement of glyphs to alternatives in the case of adding number after the glyph?
I wrote the code like this (sub a’ one by a.ss01;) and put it in a new calt, but it does not work.

How are you testing? And what do you mean by “does not work”?

I check how I usually check for alternatives. When I write 1a the glyph does not change to an alternative one.

just to confirm, you’re writing ‘a1’, and not ‘1a’ for the effect you’re after?

If you want to type 1a and get the substitution, then you’ll need to reorder the code you posted

1 Like

Are you checking in Glyphs’ Edit view?

  1. make sure you compiled the features in Font Info > Features
  2. make sure you tuend on the respective feature in the Feature button (bottom left) in Edit view
  3. make sure you have the correct feature code (see above what Rob writes)

It seems to me that I’m doing everything right. I will be very thankful for the short instructions how to try to do it right.

Can you please tell me in which app you are testing the feature? And can you send a screenshot maybe?