Avoid parsing the font twice if I’m using ttf_parser directly

[asibahi]

Hello

I cannot actually tell if this is already possible or not. If I have another dependency on ttf_parser (say for/through rustybuzz which reexports it), is it possible to avoid parsing the font twice (once through rustybuzz and once through ab_glyph)?

[alexheretic]

I don't think this is possible at the same time as avoiding breaking semver for each ttf-parser break. I believe ttf-parser font parsing is also fairly cheap.