RE: [boost] operator bool() for smart pointers

From: Bjorn.Karlsson_at_[hidden]
Date: 2002-05-08 02:07:24

> From: Darin Adler [mailto:darin_at_[hidden]]
> 
> Some people have developed a "safe_bool" idiom where you 
> define a conversion to an obscure type of pointer (a 
> particularly obscure variant of a pointer to a member) so you 
> can do "if (p)" statements, but not "int i = p" statements. 
> It's used in the Boost function library.
> 
> We might want to consider using this technique in the smart 
> pointer library. It's inelegant in implementation, but a lot 
> of people like the "if (p)" idiom.
> 
>      -- Darin

I've noticed that the current version in the CVS does exactly this. It's
really neat, as it enables a very useful idiom without sacrificing safety.

Bjorn