Re: [boost] [flyweight][parameter] is there an interest in thistemplate parameter expresion

From: vicente.botet (vicente.botet_at_[hidden])
Date: 2008-07-18 09:00:48

----- Original Message ----- 
From: "David Abrahams" <dave_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Wednesday, July 16, 2008 4:59 AM
Subject: Re: [boost] [flyweight][parameter] is there an interest in 
thistemplate parameter expresion

> This code is much too complex for me to analyze.  It would help a lot if
> you'd strip out any non-correct code, to start with.
>
> One thing I can say up front is that compilation times are a concern and
> any ease-of-use wrapper should avoid increasing them too much.

Hi,

I have attached the files striping any code not needed (and the 
flyweitht.hpp modified - need BOOST_USE_DSL_EXPR to be defined)

You are right, the compilation time is important. I expect the 
transformations I'm doing can be improved, but my knowledge of the 
metaprogramming (mpl) is not too deep.

I have done the test for the flyweight library (compiling 19 files)
WITH BOOST_USE_DSL_EXPR
real    1m3.184s
user    0m0.015s
sys     0m0.015s

real    1m3.324s
user    0m0.015s
sys     0m0.031s

WITHOUT BOOST_USE_DSL_EXPR
real    0m48.828s
user    0m0.046s
sys     0m0.000s

real    0m48.382s
user    0m0.015s
sys     0m0.031s

The compilation takes more that 30% with this wrapper.

Vicente