If you had use warnings in the script you'd see something like "my" variable $foo masks earlier declaration in same scope at scriptname.pl line 6.

I'm pretty sure that Perl is parsing the script prior to actually executing it, seeing the second declaration of $foo which masks the first declaration, and using that second variable in the same scope to actually execute the script. So you're calling the subroutine before defining the second $foo, meaning you print an uninitialized value.

You would see the same output if you had a script like

use strict;

foo();
my $foo = 2;

sub foo {
    print "foo: $foo\n";
}

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In reply to Re: Scope surprise by Nkuvu
in thread Scope surprise by smcdonald

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