RE: char equivalence classes in search - why not symmetric?

[Drew Adams <drew.adams@oracle.com>]

>   > I'd much rather we focus effort on making the equiv-classes easier to
>   > customize.
> 
> Let's not call them "equiv-classes", because that term presupposes
> symmetry.  (An equivalence relation is symmetric.)  Let's call them
> search classes for characters.

They are equivalence classes.  The chars are equivalent when searched
for (with char folding turned on).  The equivalence relation is among
the chars in the class.

This equivalence has nothing to do with the symmetry of handling them
between search string and searched text.

Whether or not they should _also_ be equivalent (handled the same way)
when used in the search string is the topic of this thread.

But even without that improvement, i.e., currently, the chars are
equivalent when searched for.

"Search classes for characters" means little.  It says nothing about
what makes them a class - what they have in common.  What they have
in common is that they are treated the same (equivalently) when 
searched for.