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Subject: Re: [boost] [contract] concepts: pseudo-signatures vs. usage patterns
From: Dave Abrahams (dave_at_[hidden])
Date: 2012-10-11 20:27:31

on Thu Oct 11 2012, Andrew Sutton <> wrote:

>> You're missing the point. I claim the associated "argument type" of
>> Predicate is char. The value type of the sequence (int) is convertible
>> to the associated argument type. That's all that's required according
>> to the text.
> Sorry... you're right. If the requirement is that the value type is
> convertible to the argument type, then yes. Fortunately that's not
> what we required in n3351.


For examples of forced conversions inserted to deal with this issue,
search for "pred" in

Looking at N3351, I wonder if you implemented these algorithms and threw
strict archetypes at the implementations. It looks very much like you
would need similar contortions.

Dave Abrahams
BoostPro Computing                  Software Development        Training             Clang/LLVM/EDG Compilers  C++  Boost

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