Re: [boost] [fusion]variadic template implications forcontainers(was Re: Variadic Templates Redux

From: David Abrahams (dave_at_[hidden])
Date: 2006-09-29 05:59:26

"Andy Little" <andy_at_[hidden]> writes:

> In the case of Fusion. I need the library to create matrices which work with 
> types other than double.

Not really.  You could have decided the abstractions provided by the
library would be too expensive and coded everything by hand.

>>> And I am not sure I totally agree.
>>
>> If you're disagreeing, I think it's because I wasn't clear.  I meant
>> that "ConceptGCC really deserves more attention than it is currently
>> getting."
>
> OK. The first question is... why?  I think I can answer that for
> myself, but what is in it for the broader audience?

Having concept support in the language revolutionizes the way we
program with templates, and in particular, provides a massively
improved experience for the casual user.

> For myself an important issue is that I am, due to inertia, compiler bound. I 
> love VC7.1. I love the IDE. (IIRC you call this ' screen scraping', but that's 
> your problem).  

No, I have never used that term, so that's your problem.  Nyah nyah.

I think IDEs are great and vc7.1 is a good compiler.

> So that is a hurdle that ConceptGCC has to face for someone like 
> me. I have my "comp.bat" file set up for checking that stuff compiles with gcc, 
> but for effortless coding, I head straight for VC7.1.  IOW your compiler/IDE has 
> a great deal of power over what you do

Yep.  That's why I am not tied to VS, as great as it is.

> And , maybe  ConceptGCC has  a similar 'problem'(It's not really a problem) to 
> the one I have with Quan, but probably more severe, in that most people are 
> bound to old C style  libraries, which frankly don't have a hope of compiling 
> with ConceptGCC, due to the average *useful* 'Hack' optimisation's that have 
> been applied. It's simply inertia again.

I don't know why you'd think that.  If the library compiles with G++,
it should compile with ConceptGCC.

> I think what C++ needs most of all, is a standard GUI, because with
> that, it would be easy to plug ConceptGCC, the compiler, into a
> standard IDE. 

That's what I do with emacs.  It works almost dreamily well.

> And with a standard IDE, it would be quite easy to
> apply a couple of switches to switch compilers...

Who needs switches?  I just hit F7 and modify the compiler name in the
command-line I have stored up for invoking bjam before hitting return.

Anyway, you can do all this compiling with bjam from within VS's IDE.
I know people do that.

> So, of all the libraries that C++ should have, I think that a standard GUI is 
> the most important, because it would be so much easier to try out and 
> demonstrate major changes to C++.

I think an easily modifiable compiler framework written in C++ would
strike lots closer to the mark than a standard GUI, for that purpose.

> Simply put, ConceptGCC needs a nice UI to show it off, and its a bit sad that 
> C++ has no way to provide that.

A nice UI to show off ConceptGCC?  I'm giggling.

> I guess that is the root of the problem.
>
> ( And I am currently concerned with trying to make some inroads into that 
> problem)

I wish you well.  I think it would be cool, but I don't think it's
going to help much with core language development.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com