I have a glyph /f_ and also /F, this doesn’t seem to be allowed for UFO since /F becomes F_.glif? What should I do?
Good question. I’ll need to ask on the RoboFab list.
But why do you need a name like this? Underscores are only used to connect names in ligatures. If your /f_ is a part that is used in a ligature, call it /f.ligaPart or something.
Turning /F into F_.glif is part of the UFO standard. I believe it comes from some filesystems (e.g., HFS+, also called Mac OS X Extended, on the Mac) not being case-sensitive. So, though “f.glif” and “F.glif” look like different filenames, they really the same file on the default filesystem on OS X.
It’s part of a calt pair to easily identify which side it’s supposed to be on, next time I’ll use a different name system