Because that's what local does! It lets you temporarily re-use the name of a package variable declared elsewhere.

Consider this expanded example:

#!/usr/bin/perl

use strict;
use warnings;

package Foo;

our $x = "blah";

package Bar;

print $Foo::x, "\n";
{
    local $Foo::x;
    print $Foo::x, "\n";
    $Foo::x = 42;
    print $Foo::x, "\n";
}

print $Foo::x, "\n";

[download]
which outputs... 
blah
Use of uninitialized value in print at loc.pl line 15.

42
blah

[download]

The first print shows the original value of $Foo::x, the second one throws an unitialized value warning because the localized version of $Foo::x has not been assigned a value. The third print gives 42 because we assigned that to the temporary $Foo::x, and the last one prints "blah" again, because the scope of the local has ended.

In reply to Re: What's wrong with this local() ? by friedo
in thread What's wrong with this local() ? by saintmike

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