From:Bryan R Harris <[EMAIL PROTECTED]>
> Jenda wrote:
> > From: Bryan R Harris <[EMAIL PROTECTED]>
> >> It makes more sense to me that (<FILE>,<FILE>) is kind of the same thing as
> >> saying (@a,@b). In list context @a returns the array as a list, but in
> >> scalar context @a returns the number of elements. Obviously (@a,@b)
> >> returns
> >> the union of the two lists, not two scalars. "<FILE>" is treated the same
> >> way.
> >
> > Almost. It still depends on the left hand side. Try this:
> >
> > @a = (10,20,30);
> > @b = (40,50,60);
> >
> > $s = (@a,@b);
> > print "$s\n";
> > #versus
> > ($s) = (@a,@b);
> > print "$s\n";
> >
> >
> > In the first case the @a and @b are evaluated in scalar context. Even
> > though they are enclosed in braces.
>
> Dang!
>
> But your example helped -- this one makes sense to me, at least:
>
> perl -e '@a=(1,2,3);@b=(4,5,6,7);@l{1,2}=(@a,@b);print "$l{1}\t$l{2}\n";'
>
> Should I think of this as: ($l{1}, $l{2}) = (@a,@b)
> ?
>
> If so, then that makes a lot more sense to me.
Right. That's it.
The fact that there is the same number of things in the braces on
both sides of the equals might be a bit confusing at first, but it's
irrelevant. Since in this case the equals provide a list context for
the (@a,@b), the two arrays are flattened into one list. So
($l{1}, $l{2}) = (@a,@b,@c);
or
($l{1}, $l{2}, $l{4}) = (@a,@b);
would be just as OK. The commas are not matched, the elements of the
two lists are. The list of specified elements of %l and the list of
all elements of @a and @b.
Jenda
===== [EMAIL PROTECTED] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery
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