They call those things iterators. An iterator is a function that returns items from a list until it runs out of them. When the list is exhausted, it returns a false value.

In Perl, they're usually written using a closure: 

sub make_iterator {
    my (@list) = @_;

    return sub {
        # return a false value if exhausted
        return unless @list;

        # return next item in list
        return shift @list;
    };
}

my $iter = make_iterator(1..5);

while ( my $val = $iter->() ) {
    print $val, "\n";
}

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In reply to Re: [stonehenge] deep copy what's the function getpwent() by Anonymous Monk
in thread [stonehenge] deep copy what's the function getpwent() by Thai Heng

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