Re: [Boost-users] boost::tribool "if ( someTriboolVar == indeterminate )" semantics is confusing

Subject: Re: [Boost-users] boost::tribool "if ( someTriboolVar == indeterminate )" semantics is confusing
From: Norbert Wenzel (norbert.wenzel.lists_at_[hidden])
Date: 2014-03-06 10:18:41

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On 03/06/2014 03:16 PM, æ£ÄÏÒ ôÒÕÛËÉÎ wrote:
> P.S. I sometimes use boost::optional<bool> to get a kind of
> tri-state value. That works without such surprises.

And fwiw it might use less memory. The simple optional<bool> stores an
additional bool to your value, whereas tribool stores an enum that
might be bigger than sizeof(bool)*2. At least that's what #7659 [0] says.

Norbert

[0] https://svn.boost.org/trac/boost/ticket/7659
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