Is perl's each function worth using?

Question

From perldoc -f each we read:

There is a single iterator for each hash, shared by all each, keys, and values

Answer 1

I think it is worth using as long as you are aware of this. It's ideal when you need both key and value in iteration:

while (my ($k,$v) = each %h) {
    say "$k = $v";
}

In your example you can reset the iterator by adding keys %h; like so:

my %h = map { $_ => 1 } qw/1 2 3/;
while (my $k = each %h) { print "1: $k\n"; last }
keys %h;  # reset %h
while (my $k = each %h) { print "2: $k\n" }

From Perl 5.12 each will also allow iteration on an array.