Re: [PATCH] [[:blank:]] only matches on SPC and TAB

[Oliver Kiddle <okiddle@yahoo.co.uk>]

Stephane Chazelas wrote:
> [...]
> > It wouldn't be ridiculous to change the documentation for this case and
> > require "unsetopt multibyte" for strict byte-by-byte comparisions, which
> > is already how it works in the vast majority of other cases.
> [...]
>
> But note that here it's not about multibyte vs singlebyte but
> whether [:blank:] honours the locale like the other POSIX
> character classes (alpha, punct...) do.

For consistency with the other character classes, I think the best is to
follow POSIX and the other shells and have [:blank:] call iswblank().
That is apply the patch plus whatever change the documentation needs to
reflect it.

I can't see it actually breaking scripts in practice. We do at least
have the option of using [$' \t'] if we want and could add [[:BLANK:]]
or similar if needed. It does seem wrong for non-breaking spaces to be
matched but that's an issue for NetBSD or whatever.

This isn't as bad as the idiocy of [a-z] matching B-Z.

> What a mess!

Indeed.

I also wish POSIX would standardise an alternative for the C locale
that's UTF-8 aware and with ISO rather than US format dates.

Oliver