It’s similar now with HarfBuzz, which I thought to use for OpenType feature support in my hacked version of the Ant typesetting program, the original OpenType support being broken. It turned out that HarfBuzz also was doing things incorrectly, and so I looked to see what was going on and discovered a comment in the code that talked about the order of application of /features. But there is no such thing in OpenType handling; features have no order, but lookups do. I think what’s going on is that people are still learning how to program for OpenType—the specs are difficult to read—and I don’t want to get involved in the process, because I can take only so much. I went back to incorporating my own (incomplete, but more correct) OpenType-handling into Ant, and that’s about as much typing as I can take—especially if I am also going to write a short novel like this posting.
(Indeed, the main reason I’m using Ant at all is that Kompostilo, building a system from scratch, was more work than I could take, and LuaTeX is too much outside my control—too much of a moving target, and too likely to make any work I do obsolete. With Ant OTOH I could simply fork off my own version, which I am doing.)
