all_keys

Split a restricted hash’s keys into visible and hidden buckets, writing the results into the caller’s arrays.

Synopsis

all_keys(%hash, @visible, @hidden);

Clears both arrays first, then fills @visible with every key that passes exists and @hidden with every legal-but-unassigned placeholder key. Returns a reference to the hash.

On an unrestricted hash @hidden comes back empty and @visible matches keys %hash. Like hidden_keys, the behaviour is experimental and depends on the current restricted-hash implementation.