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Re: UCNs-in-IDs patch
joseph@codesourcery.com (Joseph S. Myers) wrote on 17.03.05 in <Pine.LNX.4.61.0503172005230.25646@digraph.polyomino.org.uk>:
> On Thu, 17 Mar 2005, Zack Weinberg wrote:
>
> > I do not have a strong opinion on how these "spelling" properties
> > should work, but would like to point out that preserving the exact
> > spelling of identifiers is going to be a huge implementation headache
> > and I don't see that it's worth the trouble.
>
> I still consider preserving spelling to be a simple matter of correctness
> and quality of implementation; UCNs allow different spellings of the same
> identifier just as digraphs allow different spellings of # and ##. We
Let me point out strictly from a user perspective: I do agree it's QOI -
but I strongly believe the quality option is *not* preserving, here, for
the same reason that strictly preserving white space is not usually a good
idea.
> certainly not beyond the scope of GCC - and it seems obvious that
> preprocessed output should not change one UCN into another. Yes, UCNs in
Your obvious is clearly not my obvious. This is strongly counter
intuitive. The principle of least surprise demands that if what turns out
to be the same identifier is spelled two different ways, then that is a
difference that, pretty much by definition, does not matter and should not
be preserved.
You don't preserve the info that an identifier came out of token pastin
(say) either, any place the user can see it, no?
MfG Kai