in reply to Re: Re: Lexical::Alias & subroutines
in thread Lexical::Alias & subroutines

In your first example 

sub foo {
    my $x = $_[0] eq 'whatever' ? $_[1] : $_[2];
    ...
}

[download]

Seems just as effective. But in your second, I agree. I've looked enviously at the perlsub examples of using globs to avoid the need to dereference refs and wished for a way to do the same thing with lexicals. Maybe Diotalevi's Lexical::TypeGlob would work for that? I haven't gotten around to playing with it yet.

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller

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Re: Re: Re: Re: Lexical::Alias & subroutines
by Jenda (Abbot) on May 19, 2003 at 15:56 UTC

    But it is not the same. Your code creates a copy. So the changes to $x do not affect the parameters to foo().

    Lexical::TypeGlob doesn't seem to be related.

    Jenda
    Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
       -- Rick Osborne

    Edit by castaway: Closed small tag in signature

[reply]

      Right you are. I'm not having a good thread am I.

      Maybe this will make up for it -- but then again... 

      #! perl -slw
use strict;

sub doit{
    our $scalar;
    local *scalar = ($_[0] eq 'first' ? \$_[1] : \$_[2]);
    $scalar = 'new value';
}

sub double'em{
    our @array;
    local *array = $_[0];
    $_ *= 2 for @array;
}

my ($x, $y) = ('old value') x 2;
doit 'first', $x, $y;
print "$x, $y";

my @a = 1 .. 10;
double'em \@a;
print "@a";

__END__
D:\Perl\test>temp
new value, old value
2 4 6 8 10 12 14 16 18 20

      [download]
      Examine what is said, not who speaks.
      "Efficiency is intelligent laziness." -David Dunham
      "When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller
[reply]
[d/l]

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