Date: Tue, 13 Sep 2016 19:54:31 +0000 From: twilight <pipfstarrd@openmailbox.org> To: freebsd-hackers@FreeBSD.org Subject: What is the point in expression: !!var ? Message-ID: <7bf5cd37-6436-8cec-74e3-f0856bcc807c@openmailbox.org>
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Hello,
I'm digging through FreeBSD cppcheck scan report with hope to catch some
bugs.
I've came along a line:
c = cond(token, val, yylex(), noeval | !!a);
What's the point in using !! twice? Can it be deleted?
Here is the context:
static arith_t cond(int token, union yystype *val, int op, int noeval)
{
arith_t a = or(token, val, op, noeval);
arith_t b;
arith_t c;
if (last_token != ARITH_QMARK)
return a;
b = assignment(yylex(), noeval | !a);
if (last_token != ARITH_COLON)
yyerror("expecting ':'");
token = yylex();
*val = yylval;
c = cond(token, val, yylex(), noeval | !!a);
return a ? b : c;
}
--
Cheers~
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