> Yes, each does not create a list. On the other hand, it does copy the value ...

Hmmm ... so would it be fair to say that each does use less memory, even though it's slower?

> ... (and create a new scalar for the key, because the keys in hashes are not full blown scalars).

Well, actually, in my test script I was doing 

while (my (undef, $v) = each %fred)

[download]

to avoid that one (at least I hope it avoids it!), but apparently copying the values was enough to make it 6x slower, which really surprised me.

In reply to Re: Re^4: Counting keys with defined or undefined elements in a hash (behaviour of values()) by Oberon
in thread Counting keys with defined or undefined elements in a hash by Bukowski

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