Re: problem with string.format %d and very large integers

[Steve Litt <slitt@...>]

On Friday, July 29, 2011 07:30:10 AM Lorenzo Donati wrote:
> On 29/07/2011 10.54, Dirk Laurie wrote:
> > On Fri, Jul 29, 2011 at 09:22:33AM +0200, Lorenzo Donati wrote:
> >> Is there someone else that gets the same results on WinXP
> >> (32bit) with (TDM) mingw?
> >> 
> >> Any hint appreciated.
> > 
> > Install cygwin and gcc.
> 
> Thanks, but that is not an option for me. I need native Windows
> executables, without compatibility layers (moreover, at the time I
> last checked, cygwin.dll had a quite restrictive license).

Yeah, when I read the cygwin suggestion it sounded like a workaround 
that might not be practical.

I have no idea how often you need correct functionality of %d in 
string.format, but maybe, until this unexpected inconsistent behavior 
is converted to a consistent behavior, you could write your own 
decimal2string(num, width, decimalplaces) function, and then just use 
%s in string.format. Crude, ugly, should be unnecessary, but these 
things happen, and I've found sometimes the easiest thing is to write 
a workaround until the next version fixes the bug.

You could implement this function in C if practical, or otherwise in 
Lua if where it's deployed can't compile C. The C would obviously be 
faster and perhaps easier (I think you just use itoa() or ltoa or 
sprintf() with a %f or something similar), but if you don't use this 
function all over the place or in tight inner loops, the speed 
differential would be meaningless.

HTH

SteveT

Steve Litt
Author: The Key to Everyday Excellence
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