Re: chaining statements without a semicolon

From:
Joe Greer <jgreer@doubletake.com>
Newsgroups:
comp.lang.c++
Date:
Wed, 10 Oct 2007 22:25:47 +0200 (CEST)
Message-ID:
<Xns99C5A7221FE54jgreerdoubletakecom@194.177.96.78>
jcktmp@gmail.com wrote in news:1191956419.789292.195680@
57g2000hsv.googlegroups.com:

I currently have a macro for logging with a definition similar to the
following:

#define LOG shouldLog() && logStream

so that statements of this type may be written:

LOG << "some logging << endl;

I would like to add a static variable to this macro, so that the macro
expands to:

static LogObject x; x.shouldLog() && logStream

The problem is that with control statements that optionally use braces
(if, while, etc.), the multi statement approach doesn't work. Is there
any way to rewrite this (without adding a brace to the log macro and
creating an END macro) so that everything can be done in LOG?

Thanks,
J


That won't work, but you can use the singleton pattern. That is:

#define LOG LogObject::Instance().ShouldLog && LogObject::Instance
().logStream

would work.

Depending upon how you implement your Instance() method, you could have
one per file or one per application.

joe

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