The following code produces two different results if you comment out the "my" statement that defines the variables. Why should it matter? What's going on that I'm not getting? Are there now two sets of each variable, even tho they have identical names? And most importantly, what is the scope of the new variables that are sprung into existence within the "foreach" loop that's doing the assignments? I want to "use strict" and am unsure of the implications. I want to make sure the variables that are used do not conflict with globals (from packages). Hence the desire to use "my". So, what gives? 
my $n = 0;

my ($zero, $one, $two, $three );  #### This is the "my" in question
foreach ( qw( zero one two three ) ) {
    $$_ = $n++ || "zero";
}
my $msg = "";
foreach ( qw( zero one two three ) ) {
    $msg .= "$_ = '$$_'\n";
}
print $msg;

print qq(
zero = '$zero'
one = '$one'
two = '$two'
three = '$three'
);

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In reply to when is "my" not necessary? by argv

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