Hello citi2015,

I meant Perl’s design decision to remove the aliasing when @_ is assigned-to within a subroutine.

You can, of course, do the swap by explicitly accessing the subroutine arguments as individual elements of @_:

sub swap
{
    my $temp = $_[0];
       $_[0] = $_[1];
       $_[1] = $temp;
}

[download]

— but note the necessity of “remembering” the initial value of $_[0] by storing it in a temporary variable. And I think that answers my question: if the aliasing were not removed, @_ = reverse @_ would produce wrong results, because some elements would be changed (assigned-to) before they were assigned-from.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re^3: Accessing Arguments inside Subroutines via @_ by Athanasius
in thread Accessing Arguments inside Subroutines via @_ by citi2015

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