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From: Andy Little (andy_at_[hidden])
Date: 2006-09-22 21:40:16

"Joel de Guzman" <joel_at_[hidden]> wrote in message
> Andy Little wrote:
>> "Joel de Guzman" <joel_at_[hidden]> wrote in message
>> news:ef1t83$bhv$
>>> Andy Little wrote:
>>>> "David Abrahams" <dave_at_[hidden]> wrote in message
>>>>> AFAICT the name ftag should be changed to something more descriptive
>>>>> and more certainly unique, e.g. boost_fusion_iterator_tag. Is there
>>>>> a reason it needs to be so short?
>>>> Why make such a trivial change to the interface post review? AFAICS now
>>>> is
>>>> too
>>>> late, and will cause unnecessary pain to users.. like myself.
>>> Well, actually, it shouldn't be a part of the interface.
>>> Here, I'm used to calling it the f#%$tag :) It's not supposed
>>> to be for public consumption, and I intend to enforce that.
>>> Either way, it's not a good name (especially for minors. ;)
>>> and it must be changed.
>> And BTW its pretty public in the 'make your own iterator" part of the docs.
> Yeah. That's unfortunate. I asked Dan to fix it. Anyway, I suggest you
> do the right thing: specialize tag_of.
>> So far I have made 5 fusion style iterators. Next is the matrix minor
>> iterator,
>> which extracts minors from a matrix, as a prelude to extracting cofactors.
> Cool!
>> Fusion::Views are wonderful things ....
> Views are wonderful things. If you remember, I mentioned this idea
> about a const string library using Fusion like views. I'm betting
> such a library will rock in terms of performance.

hmmm.. Fusion is a bit wasted on strings ( I only need them for output, what is
slow as a dog anyway) AFAICS. Seems to be "quite" good at inlining generic
matrix concatenation though ... Actually I can't see how I would speed the
output of my current efforts, once optimised by VC8 express, even if I coded
each instantiation by hand :-)

There do seem to be limits to when the compiler will optimise a view though, It
may have something to do with copying references(aka joint-view) as raw bytes,
after which AFAICS the compiler will treat them as pointers. that said that is
only an impression so far.

Andy Little

Andy Little

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