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Subject: Re: [boost] [parameter] BOOST_PARAMETER_CONSTRUCTOR bug
From: Nathan Crookston (nathan.crookston_at_[hidden])
Date: 2013-06-10 11:20:59

James Hirschorn wrote:

> Cromwell Enage wrote
> > Hello, James.
> >
> > In order to enable argument deduction, you need to augment your parameter
> > declaration clause with either an explicit type or a Unary Metafunction
> > Class--essentially an MPL Lambda Expression--that returns mpl::true_ when
> > the argument type fulfills the requirements you want to impose on it.
> Try
> > one the following macro invocations:
> > ...
> Have you tried to compile your examples? They both fail for me, with the
> exact same error as the original.
> Also, I have read the documentation many times, and did not notice the
> requirement you mentioned.

I agree with Cromwell, to have a hope of working, you'd have to some way of
identifying the expected type of the argument to have a hope of deducing it.

However, I haven't found a syntax that works here either -- my suspicion is
that deduced constructor parameters aren't currently supported. Certainly
there aren't any tests which validate such functionality, and no
documentation regarding it either. Unfortunately, a cursory glance through
the code wasn't very illuminating -- it would take me some serious study to
really understand the code.

Hopefully I'm wrong and a maintainer will be able to set us straight.


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