Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!purdue!bu-cs!buengc!bph
From: bph@buengc.BU.EDU (Blair P. Houghton)
Newsgroups: comp.lang.c
Subject: Re: C history question
Message-ID: <4153@buengc.BU.EDU>
Date: 15 Sep 89 01:18:21 GMT
References: <575@calmasd.Prime.COM> <10839@riks.csl.sony.co.jp>
Reply-To: bph@buengc.bu.edu (Blair P. Houghton)
Followup-To: comp.lang.c
Organization: Boston Univ. Col. of Eng.
Lines: 20

In article <10839@riks.csl.sony.co.jp> diamond@riks. (Norman Diamond) writes:
>In article <575@calmasd.Prime.COM> wlp@calmasd.Prime.COM (Walter Peterson) writes:
>
>>C has bitwise operators for AND (&), OR (|) and XOR (^) and boolean 
>>operator for AND (&&) and OR (||), but not for XOR (^^). Why?
>
>In A && B, if A is false (0) then B is not evaluated.
>In A || B, if A is true (non-0) then B is not evaluated.
>In A ^^ B, for which value(s) of A do you skip B?

You never do.  So what?  So it's a boolean xor, instead of a
short-circuiting operator.  It returns 1 or 0 depending on the
result of the boolean comparison.  Try getting that out of (A ^ B)
every time.  Without doing (!!(A ^ B)), I mean.

I mean, what's the biggie about having &&?  We _could_ just do
(A ? !!B : 0), but would you want to?

				--Blair
				  "I mean, I suh-wear.."