"I don't know why a sub() in general would create a hash, only to just pass back just the keys?"

There are likely to be lots of reasons, but a simple one is to generate a list of unique results from some process.

Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond

In reply to Re^4: Using 'keys' on a list by GrandFather
in thread Using 'keys' on a list by lammey

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