Re: [boost] [review] Convert library

Subject: Re: [boost] [review] Convert library
From: Andrzej Krzemienski (akrzemi1_at_[hidden])
Date: 2014-05-26 04:31:53

2014-05-26 10:12 GMT+02:00 Vladimir Batov <vb.mail.247_at_[hidden]>:

> Joel de Guzman wrote
> > On 5/25/14, 6:34 PM, Jeroen Habraken wrote:
> >  > ...
> >  > [4] http://www.kumobius.com/2013/08/c-string-to-int/
> >
> > This makes me wonder. How fast is Convert BTW? How does it compare
> > to the examples in that benchmark? Boost is performance hungry! It
> > will be a real cause of concern if it is slower than the benchmarks.
>
> "convert" has no benchmarks of it own... because it does nothing. :-) It's
> a
> "manager" class rather than a "worker" class. It's merely an interface to
> coordinate/unify and uniformly deploy (or quickly swap on when-needed
> basis)
> varying conversion facilities. So, with the "coerce"-based converter
> "convert" performs as fast as "coerce". I actually ran tests with
> lexical_cast and others: naked lex_cast vs. convert+lex_cast. No
> performance
> degradation. I mention it in the docs.
>

Can this be true? Your converter concept returns a (small) bool. The API
returns something like optional<T> (likely something significantly bigger
than bool). This alone could add to performance hit. Worth measuring, at
least.

Regards,
&rzej