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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: list of chars to introduce in future c
Date: Thu, 14 Feb 2019 12:20:11 -0800
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David Brown <david.brown@hesbynett.no> writes:
[...]
> Making the minus sign part of the integer or floating point constant
> does not require a new symbol - it would just need a tweak in the
> lexical parsing rules.

It would need a fairly major tweak if we want to avoid breaking
existing code.

In all current versions of C, `1-1` consists of three tokens and
parses as an additive-expression.  If `-1` were a single token,
maximal munch implies that `1-1` would consist of two tokens (and
woud produce a syntax error).

You could add rules for disambiguating whether `-1` is a negative
constant or a `-` followed by `1`, but the rules would have to depend
on the current parsing state, not just on the current lexical state.

(A similar problem led to the pre-ANSI change from `=-` to `-=`.)

Incidentally, I've found that fir's contributions to this
newsgroup are mostly noise, so I never see his posts.  I suggest
that responding to his posts merely adds more noise.  I ask you to
curb your impulse to feed the trolls.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */