Re: BUG #15548: Unaccent does not remove combining diacritical characters

Tom Lane wrote:

> Hm, I thought the OP's proposal was just to make unaccent drop
> combining diacriticals independently of context, which'd avoid the
> combinatorial-growth problem.

In that case, this could be achieved by simply appending the
diacriticals themselves to unaccent.rules, since replacement of a
string by an empty string is already supported as a rule.
It doesn't seem like the current file has any of these, but from
https://www.postgresql.org/docs/11/unaccent.html :

"Alternatively, if only one character is given on a line, instances
of that character are deleted; this is useful in languages where
accents are represented by separate characters"

Incidentally we may want to improve this bit of doc to mention
explicitly the Unicode decomposed forms as a use case for
removing characters. In fact I wonder if that's not what it's
already trying to express, but confusing "languages" with "forms".

Best regards,
--
Daniel Vérité
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