Language-dependent glyphs other than CJK?

Question

For those not familiar with Han unification, Unicode uses the same codepoints to encode CJK characters as used in Chinese and Japanese, even when they look slightly different. This has spurred some controversy, since the characters look "wrong" if the default font of the user doesn't match the intended language, unless one uses metadata to specify the language (e.g. the HTML "lang" attribute).

Leaving pros and cons of Han unification aside, are there any other (non-CJK) examples of glyphs that look (or should look) different depending on the language? Failing that, perhaps there are historical examples where that used to be the case?

Answer 1

There are quite a few examples, even within the roman script. The OpenType font standard has a feature tag for this very purpose: locl. There is also diachronic variance, hence hist.

The most prominent examples are not the base letters, though, but diacritic marks. The French accent acute is flatter than the Polish kreska, for instance, though coded the same. On the other end, there is no proper justification by way of a minimal pair to treat cedilla, ogonek and comma below as separate diacritics. A written language that has only one kind of diacritic, say German umlaut double dots, will allow much stylistic variation thereof (e.g. look like macron, tilde, double acute etc.) which would be different letters in other languages, say Hungarian.