my creates a new variable which is only valid inside a sub or block
Yes, to be more accurate: my creates a variable that exists till the end of the innermost enclosing block.
local uses the global var and saves its original value and you can give it a new value which is also only valid inside a sub or block
Yes, and the value exists till the innermost enclosing block is exited.
So..... both create a new variable.
How did you draw that conclusion? In your description of local you say it uses the global variable, and saves its original value, giving you a new value. That's correct - it uses the global variable.

The following is an easy reminder of the difference:

my creates a new variable; local creates a new value.

Note also that a myed variable isn't visible outside the block it's declared in, while a localized value is: 

#!/usr/bin/perl

use strict;
use warnings;

use vars '$global';
my $lexical;

$global  = 'outer';
$lexical = 'outer';

sub show {
    printf "\$global is '%s'; \$lexical is '%s'\n", $global, $lexical;
}

show;

{
    local $global = 'inner';
    my $lexical   = 'inner';
    show;
}

__END__
$global is 'outer'; $lexical is 'outer'
$global is 'inner'; $lexical is 'outer'

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In reply to Re: difference between my and local by Perl Mouse
in thread difference between my and local by jeanluca

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