On 11/1/11 Tue Nov 1, 2011 12:02 PM, "rent0n" <ren...@gmx.com> scribbled:
> Hi all,
>
> Can somebody please explain what is the difference between:
>
> sub subroutine {
> my $var = @_;
> ...
> return 1;
> }
>
> and:
>
> sub subroutine {
> my ($var) = @_;
> ...
> return 1;
> }
>
> I think it's something related to the context but I'm not completely
> sure. What I know is that to have the behaviour I want I have to declare
> the variable like in the second example (with parentheses).
> This confuses me a bit because it's not the way I usually declare
> variables in my main program (that is, without parentheses).
You are correct: it has to do with context. In the statement
my $var = @_;
the context of the assignment is scalar. Therefore, under the rules of Perl,
an array evaluated in scalar context returns the number of elements, which
is then assigned to $var.
In contrast, in the statement
my( $var ) = @_;
the context of the assignment is array (or list), therefore elements on the
left-hand-side get assigned to their equivalent positions on the
right-hand-side, so $var is assigned the first element of the array @_;
--
To unsubscribe, e-mail: beginners-unsubscr...@perl.org
For additional commands, e-mail: beginners-h...@perl.org
http://learn.perl.org/
