It's not clear to me exactly what you're trying to do, but you've sinned against a big no-no:

Do not modify an array in a foreach loop over the same array.

What I do, if I don't mind the array being eaten in the process, is something like this:

$\ = "\n";  # append newline after print
@a = 'a';
while(@a) {   # there's stuff left in the array
    my $item = shift @a;  # remove it, ready to process
    print $item;
    if(rand() < 0.8) {
        # sometimes add a new item
        push @a, ('a' .. 'z')[int rand 26];
    }
}
[download]

Example output:

a
p
i
n
o
q
e
p
k
[download]

You see? while doesn't mind at all if the item to loop over, changes under it. foreach does.

That's one way that you can, for example, replace a recursive implementation of a file digger that does something like File::Find, with an iterative one: just push new directories you encounter while processing a directory, onto the to-do array.

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