Since it's been raised a few times, I'll provide a bit more information on the bigger picture.

We have a script that does a chunk of processing and populates the results in a hash. The hash is then used for more processing in a few places, some of which are expensive.

I wanted to be able to test the expensive bits of code with a smaller hash (taken from the real data), without having to touch each occurrence where the hash was used, so I figured modifying the hash in place would be acceptable, either by creating a temporary hash or deleting a hash slice.

Early experiments involved testing slices like (keys %hash)[5..-1], but didn't go very far. Will have to read up on array indexes and slices a bit more.

Thanks for the suggestions. Good to get a wider perspective on possible variations and solutions.

In reply to Re^2: Delete all hash keys except for n of them by Anonymous Monk
in thread Delete all hash keys except for n of them by Anonymous Monk

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