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22 Sep
2009
22 Sep
'09
6:15 a.m.
Hans Hagen
so, its not that frac itself is the problem dealing with in the engine, because if so, many features would be a problem, it's just that font makers stick to a couple of simple rules like:
(1) replace all <digits> <slash> <digits> by <sup digits> <overlapping frac slash> <sub digits>
(1) replace all <digits> <slash> <digits> by <sup digits> <overlapping frac slash> <sub digits>
and if they have rule 2, it will mess up things like a/b
Is rule (2) missing? I see (1) twice. Are there fonts that have a or b in the "numr" and "dnom" features but where they do not work in "frac"?