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From: Sebastian Huber <sebastian-huber@web.de>
To: gcc-help@gcc.gnu.org
Subject: Re: Lexical conversion.
Date: Wed, 16 Oct 2002 12:20:00 -0000
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On Wednesday 16 October 2002 06:03, Moore, Mathew L wrote:
> > > #include <sstream>
> > >
> > > string convert (const int number) {
> > >      ostringstream ostr;
> > >      ostr << number;
> > >      return ostr.str ();
> > > }
> >
> > Sigh! I decided (especially as most the cases I worry about
> > are in 0-9) to
> > implement it like so.. (I unit tested it so I'm reasonable
> > confident it
> > works and its about 3 times faster in the general case than
> > using printf)
>
> Why do you suppose there is such a great speed improvement with the code
> below?  It seems to me that snprintf() should be able to optimize this ta=
sk
> quite effectively.  The only overhead should be the parsing of the format
> string, which in this case would be very simple.
>

If you can use <sstream> you should prefer it. Stringstreams are likely the=
=20
most general and efficient way to do such conversions with C/C++. If you kn=
ow=20
more about the input, you can optimize of course.

Ciao
	Sebastian