Re: [boost] 3-state boolean type

From: Rob Stewart (stewart_at_[hidden])
Date: 2002-08-02 13:01:33

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From: "Peter Dimov" <pdimov_at_[hidden]>
> From: "Rob Stewart" <stewart_at_[hidden]>
> > From: "William E. Kempf" <williamkempf_at_[hidden]>
> > >
> > > bool b();
> > >
> > > initializes b to false.  So I'd think the  default ctor should
> initialize
> > > the state to false.
> >
> > That doesn't invoke the default ctor.  You'd have to do something like
> this:
> >
> >    bool b(bool());
> 
> bool b(); // function, no arguments, returns bool
> 
> bool b(bool()); // function, one argument bool (*) (), returns bool

Ah, yes.  I'd forgotten that.

> bool b = bool(); // value-initialized bool

That's what I should have said knowing that the initializer syntax is
problematic in this respect.  Oh well.

> bool b((bool())); // ditto

See, "b((bool()))" is "something like" "b(bool())," like I said.  I wasn't
confident that I had the right syntax, so I waffled with "something like."  I'd
forgotten the magical incantations since I never do that, so I didn't want to
say anything more than "something like."

Thanks for the clarification.

-- 
Rob Stewart                           stewart_at_[hidden]
Software Engineer                     http://www.sig.com
Susquehanna International Group, LLP  using std::disclaimer;