This implementation of itoa is rather fast and open-source, based on a lookup up table of groups of four digits: https://sourceforge.net/projects/itoa "Fast implementation of the old deprecated itoa(), lltoa() etc... plus some C++ wrapping. Theoretically controversed but practically very useful." The source is visible here, with a humble attempt to integrate it into Boost : http://itoa.cvs.sourceforge.net/viewvc/itoa/itoa/ Thorsten Ottosen wrote:
Darren Garvey skrev:
2008/12/3 David Abrahams <dave@boostpro.com>
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://lists.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 _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost