Compatibility decomposition for Hebrew and Greek final letters

Eli Zaretskii eliz at
Thu Feb 19 14:17:30 CST 2015

> From: Philippe Verdy <verdy_p at>
> Date: Thu, 19 Feb 2015 20:31:07 +0100
> Cc: Julian Bradfield <jcb+unicode at>, 
> 	unicode Unicode Discussion <unicode at>
> The decompositions are not needed for plain text searches, that can use the
> collation data (with the collation data, you can unify at the primary level
> differences such as capitalisation and ignore diacritics, or transform some
> base groups of letters into a single entry, or make some significant primary
> difference when there are diacritics (for example in German equating 'ae' and
> 'ä' at the primary level).

Sorry, I disagree.  First, collation data is overkill for search,
since the order information is not required, so the weights are simply
wasting storage.  Second, people do want to find, e.g., "²" when they
search for "2" etc.  I'm not saying that they _always_ want that, but
sometimes they do.  There's no reason a sophisticated text editor
shouldn't support such a feature, under user control.

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