Re: fullfactor is not loaded in 2.5.0

[Bill Allombert <Bill.Allombert@math.u-bordeaux1.fr>]

On Mon, Jun 06, 2011 at 10:16:10PM +0200, Bill Allombert wrote:
> On Mon, Jun 06, 2011 at 11:45:10PM +0400, Max Alekseyev wrote:
> > Dear Jeroen and pari-users,
> > 
> > I'm trying to use fullfactor package from
> > http://cage.ugent.be/~jdemeyer/computer/fullfactor.html
> > in the development version 2.5.0 of PARI/GP but it reports an error:
> > 
> > ? \r fullfactor.gp
> >   ***   unexpected ';': ...accum=accum+1);if(accum++;accum>=numaccum,my(
> >   ***                                               ^--------------------
> > 
> > So, my question is whether this is intended behavior and fullfactor has to
> > be updated to work with PARI/GP 2.5.0, or something got broken and needs to
> > be fixed in 2.5.0 instead.
> 
> As far as I know, using ';' in the condition of the 'if' statement is not valid
> and never has been in a stable version. This worked in PARI 2.4.2 and 2.4.3 but
> only as a side-effect of the implementation and this was not documented. This 
> has been fixed in SVN 13155. Sorry for the trouble.

Today I found a good reason to forbid it...
If you mistakenly write a semicolon instead of a comma, your if() condition will
be wrong but look correct:
s=0;for(i=0,15,if(i^2%16==1;s++));s
->16 instead of 4

Cheers,
Bill.