RE: [boost] Review: concept checks.

From: Jeremy Siek (jsiek_at_[hidden])
Date: 2000-11-20 11:11:46

Wow, thanks :)

On Mon, 20 Nov 2000, Moore, Paul wrote:
> 
> The usual reason for do...while is that {...} is not "quite" a statement.
> Example
> 
> #define test1 do { int n = 2; (void)n } while (0)
> #define test2    { int n = 2; (void)n }
> 
> if (0)
>     test1;
> else
>     /* whatever */;
> 
> if (0)
>     test2;
> else
>     /* whatever */;
> 
> The second fails (dangling else) as test2; expands to {...}; and the extra ;
> is a null statement which stops the else from coming straight after the
> if...
> 
> I'm depressed that I know this...
> Paul.

----------------------------------------------------------------------
 Jeremy Siek                        www: http://www.lsc.nd.edu/~jsiek/
 Ph.D. Candidate                  email: jsiek_at_[hidden]
 Univ. of Notre Dame         work phone: [phone]
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