MakeOTF Error by exporting font

Hi!

This is my first time using glyphs and I’m getting alway the makeOTF [FATAL] error. Lookup type different from previous rules in this lookup block [features.fea 189] by trying to exporting the font.

I checked out this tutorial https://glyphsapp.com/tutorials/troubleshooting-a-font-that-does-not-export

but I can’t solve the problem that GLYPH is talking about.

I only tried to add a single glyph to a existing font. Its meant to be a longer version of the “emdash” like you see in the screenshot below.

Could you help me to fix it?![19|690x244]

You cannot mix different ‘lookup types’, i.e., different kinds of substitutions, for instance single substitution (e.g. sub x by x.alt;) with contextual (e.g. sub a b' by b.alt;). Instead, you will need to separate them in different lookups, e.g. like this:

lookup singleSubs {
  sub x by x.alt;
  sub y by y.alt;
  sub z by z.alt;
} singleSubs;

lookup contextualSubs {
  sub a b' by b.alt;
  sub c d' by d.alt;
} contextualSubs;