You can find the number of elements using keys in a scalar context, and it won't take time or space to go through the elements.

But you could use the recipe for printing a random line from a file to just iterate through the hash without knowing how many elements it has and select a random one.

Yes, as long as you don't change the hash, keys will return keys in the same order every time. values will return values in the corresponding order.

Caution: Contents may have been coded under pressure.

In reply to Re: Random hash element (low memory edition). by Roy Johnson
in thread Random hash element (low memory edition). by amarquis

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