Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!leah!itsgw!steinmetz!uunet!vicorp!charlie
From: charlie@vicorp.UUCP (Charlie Goldensher)
Newsgroups: comp.lang.c
Subject: Re: type of character constants
Summary: Why should we care?
Keywords: character constants
Message-ID: <1644@vicorp.UUCP>
Date: 10 Mar 89 16:42:23 GMT
References: <13068@steinmetz.ge.com> <102@servio.UUCP> <10138@socslgw.csl.sony.JUNET> <1783@dlvax2.datlog.co.uk> <3711@xyzzy.UUCP>
Reply-To: charlie@vicorp.UUCP (Charlie Goldensher)
Followup-To: comp.lang.c
Organization: V. I. Corporation, Amherst, Massachusetts
Lines: 37


In article <3711@xyzzy.UUCP>, throopw@agarn.dg.com (Wayne A. Throop) writes:
> > scm@datlog.co.uk ( Steve Mawer )
> >> diamond@diamond. (Norman Diamond)
> >> When you assign 'x' to a character, you are assigning an int to a
> >> character.  The reader knows that the type mismatch was intentional.
> > Not if he knows the C language.  A single character written within
> > single quotes is a *character constant*.  This isn't an int.
> 
> Ha.  A lot Steve knows.  From K&R, 1st ed, pg 185
> 
>     Character constants have type int; floating constants are double.
> 

The paragraph from which this is excerpted is as follows:

	A constant is a primary expression.  Its type may be int,
	long, or double depending on its form.  Character contants
	have type int; floating constants are type double.

On the previous page (page 184, 6.6 Arithmetic conversions) K&R say:

	First, any operands of type char or short are converted to
	type int, and any of type float are converted to double.

So what does it matter if a character constant is of type char or of
type int?  If it is of type char, it will be *converted* to type int
in any expression in which it is used.  And if it is of type int it
will be implicitly cast to type char if it assigned to a variable of
type char.

I don't care how the compiler writer chooses to implement it internally
as long as they follow the appropriate conversion rules.

Is there some reason I *should* care?
-- 
charlie@vicorp.uu.NET	--	Charlie Goldensher