Re: [boost] Re: Is there plans to make stand-alone functor traits?

From: Ullrich Koethe (u.koethe_at_[hidden])
Date: 2001-04-05 18:45:22

> Okay, you can do that, usually at the cost of usability for the client...

I'm not sure if usablility is so bad, especially in the keyword variant.
I keep forgetting the argument order even for my own functions. Keywords
would solve this (as long as I remember them :-). Also, they give much
more powerful default value capabilities than C++ otherwise has. 

I'm using a similar technique in the vigra library:

transform(srcImageRange(in1), srcImage(in2), destImage(out), Functor());

where srcImageRange() etc. are factories for argument tuples (of fixed
length in this case). This greatly improves readability.

> but it still doesn't handle the const/non-const reference combinatorics
> problem.

What exactly is this problem? Can it be solved by explicitly
specializing the list() factory?

list<Foo &>(aFoo) vs.
list<Foo const &>(aFoo)

Anyway, it would certainly be better to build these capabilities into
the language (I was pleased to here about Bjarne's plans)

-Ulli

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| Ullrich Koethe  Universität Hamburg / University of Hamburg    |
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