Subject: Re: [boost] lexical_cast optimization
From: Thorsten Ottosen (thorsten.ottosen_at_[hidden])
Date: 2008-12-04 05:04:11
Darren Garvey skrev:
> 2008/12/3 David Abrahams <dave_at_[hidden]>
>
>> Someone was asking me today about the inefficiency of lexical_cast for
>> its common itoa/atoi-like usage, and it occurred to me that it could
>> *easily* be optimized to handle the common cases by dispatching to
>> itoa/atoi ftoa/atof where available, and even sprintf. Seems like a
>> great idea to me.
>>
>> Thoughts?
>>
>
> You may find the following interesting:
>
> http://listarchives.boost.org/Archives/boost/2007/11/131001.php
>
> I'd quite like to know if Johan got these changes into the library. Any news
> on this?
>
I haven't looked at the implementation, but I know Matthew Wilson had a
series of articles in CUJ about fast string to integer conversions.
IIRC, he was doing much better than the functions from the C library:
http://www.ddj.com/cpp/184403874
I guess it might be possible to optimize the floating point casts too,
albeit it might be somewhat harder.
-Thorsten