RE: [tcltk-perl] return of 1=>1.0 transformation error

[Jeff H. <je...@Ac...>]

> > my $row = 0;
> > foreach my $leaf('Tk.xbm','Xcamel.gif')
> >  {
	...
> >   my $col = 0;
> >   $mw->Label(-text  => 'Initial')
> > 	->grid(-row => $row, -column => $col);
> >   $mw->Label(-background => 'white',-image => $src)
> > 	->grid(-row => $row+1, -column => $col++);
> > 	...
> > 
> > We see that the problem is at -row 1, so that last line is the issue.  
> > That this becomes SvNOK w/o being SvIOK in Perl 5.6 seems "just wrong" 

> Perl 5.6.1 doesn't do anything weird there for me.  Maybe it it the
> grid() method that modifies the SV?

grid only ever passes the args through, and this is only ever
touched by the C internals.  That means it goes through the
same path when == 0 as == 1.  It's possible that this code:

	if (SvIOK(sv) && ((double)(ival = SvIV(sv)) == dval)) {

returns different results for 0 as 1.0, but a quick C check
with this:

    int ival = 1;
    double dval = 1.0;
    printf("%d\n", (((double)(ival = (int)dval)) == dval));

Says it should convert back and forth OK (that shows '1').  I
know you will have issues with incorrect double equality on
some corner cases.

> You can investigate this using Devel::Peek.  It is not part 

I only have 5.8 installed, so it always works for me.  Perhaps
Vadim would like to hunt this down?

Jeff