Newsgroups: comp.lang.c
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: token pasting (was: how widespread is this cpp bug?)
Message-ID: <1988Dec5.195231.3658@utzoo.uucp>
Organization: U of Toronto Zoology
References: <49179@pyramid.pyramid.com> <6625@csli.STANFORD.EDU> <9026@smoke.BRL.MIL> <1747@solo3.cs.vu.nl>
Date: Mon, 5 Dec 88 19:52:31 GMT

In article <1747@solo3.cs.vu.nl> maart@cs.vu.nl (Maarten Litmaath) writes:
>Why didn't the ANSI committee legalize that current practice, instead of
>defining a new paste operator (##)?

Because that current practice was current practice only on some compilers;
on others it did not work and could not easily be implemented.  In
particular, it is hard to make it work under a token-based preprocessor.
It's also hard to define in a precise way that doesn't cause trouble with
other things.  (He who does not value a precise definition of this stuff
has never tried to implement it.)
-- 
SunOSish, adj:  requiring      |     Henry Spencer at U of Toronto Zoology
32-bit bug numbers.            | uunet!attcan!utzoo!henry henry@zoo.toronto.edu