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Subject: Re: [cfe-dev] Is that getting wchar_t to be 32bit on win32 a good
 idea for compatible with Unix world by implement posix layer on win32 API?
Date: Sat, 9 May 2015 12:36:45 +0200
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* John Sully <john@csquare.ca> [2015-05-09 00:55:12 -0700]:
> In my opinion you almost never want 32-bit wide characters once you learn
> of their limitations.  Most people assume that if they use them they can
> return to the one character -> one glyph idiom like ASCII.  But Unicode is

wchar_t must be at least 21 bits on a system that spports unicode
in any locale: it has to be able to represent all code points of the
supported character set.

in practice this means that the only conforming definition to iso c
(and thus posix, c++ and other standards based on c) is a 32bit wchar_t
(the signedness can be choosen freely).

so the definition is not based on what "you almost never want" or what
"most people assume".

if the goal is to provide a posix implementation then 16bit wchar_t
is not an option (assuming the system wants to be able to communicate
with the external world that uses unicode text).