[boost] Re: inert_bool

From: Daniel Frey (daniel.frey_at_[hidden])
Date: 2003-09-08 09:11:18

Ed Brey wrote:
> Douglas Gregor wrote:
> 
> Unless I missed something bool_testable only provides half the problem: it provides operator!, but not the implicit bool conversion.

I hope you missed something, because bool_testable means that you write 
an operator bool() yourself and bool_testable makes it as safe as the 
safe-bool-idiom. You have to provide something anyway, so why not the 
most obvious operator bool() as this is actually what you are trying to 
achive, isn't it? The problem is usually that this is not safe enough, 
but bool_testable provides exactly that.

It does so by providing a private operator int() which means that 
conversions to bool use your operator bool() as expected (and as 
efficient as, well, operator bool()) and all other conversions (to int, 
float, ...) are either an access violation (as operator int() is 
private) or ambiguous.

I think you should have a closer look at bool_testable and give it 
another try. If you have further questions, I hope I can answer them :)

Regards, Daniel

-- 
Daniel Frey
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