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Postings from October 2011
> What about normalization, etc.
>
>
> https://rt.perl.org:443/rt3//Public/Bug/Display.html?id=96814
>
> I had a branch somewhere that implemented a very simple pragma (use
> normalized identifiers => "NFD"), which started off pretty well, but I
> quickly got stumped as I couldn't get direct stash manipulation right
> in all cases.
> That "worked" (for some definitions of working, of course :P) by
> calling Unicode::Normalize::normalize, but a final implementation
> should probably inline some normalization form into the core, and use
> Unicode::Normalize::normalize as a fallback.
>
Unicode Standard Annex #31 Unicode Identifier and Pattern Syntax
recommends NFC rules prevail.
I would like to suggest that in the scope of a 'use utf8' any identifier
added to the stash or a pad is passed through Unicode::Normalize::NFC
before being so added. This could be done by making the stash and pad
magical when adding or manipulating a key.
This has the following benefits/costs
1) Individual scripts and packages may be in any normalisation form
but identifiers will be compared in a known way
2) Anything not using utf8 will still be backwardly compatible.
3) Anyone comparing an element in the stash or pad to a string under
'use utf8' will have to normalize the string before comparison. But
If you are playing at that level I would like to assume that you
know what you are doing.
4) Exporter and Sub::Exporter and friends will now have to take
account of the utf8-ness of the environment and normalize their
parameters appropriately. I decided to do it this way rather than
force 'import' to do an implicit normalization as at this level of
Wizardry you should be able to do your own magic and not have things
forced on you.
John
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