Re: [boost] [Potentially OT] String Concatenation Operator

Subject: Re: [boost] [Potentially OT] String Concatenation Operator
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2010-08-26 12:47:15

On 26/08/10 15:19, Jeffrey Lee Hellrung, Jr. wrote:

>> You can't get the size of a range at compile-time.
>
> But you can define a trait or metafunction that tells you *whether* the
> range has a compile-time size (and, if so, then *what* that size is)

You might as well special case fusion sequences.

> and go around specializing it for C arrays, Boost.Array, the Boost.Range
> adaptors, etc. E.g., a transformed range is statically sized iff it's
> underlying range is statically sized; a joined range is statically sized
> if *all* its underlying ranges are statically sized; etc.

Indeed, you could specialize all range adaptors to call the fusion 
equivalent when passed fusion sequences, but then it wouldn't be clear 
what the return type is, since an iterator adaptor and a fusion 
expression are quite different things.

This is already a problem with ranges, as return types are not well 
documented (and sometimes are in a detail namespace...). This could be 
solved with a result_of namespace like fusion does.