The difference between my and local is just one of scope. All subroutines called from the context of a local variable can access that variable, but not the my variable: 
sub foo {
    local $a = 10;
    my $b = 20;
    bar();
}

sub bar {
    print "A: $a\n"; # Just fine
    print "B: $b\n"; # Warning from -w
}

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If a piece of code needs to use local in this way, it's could probably be rewritten in a cleaner way. If my works, you should definitly use it.

I won't condemn all use of local, however. I believe there are situations where you need to use local for dynamically generated anonymous functions, perhaps for use with $SIG{XYZ}. Can anyone confirm or deny this? I just remember writing signal code once where I needed to use local. (Of course, this is before I learned about the signal handling packages at CPAN.)

-Ted

In reply to Scope Difference by tedv
in thread I need a simple explantion of the difference between my() and local() by Jemts

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