You are right, absolutely. I have found this solution hour after sending. Really, we sould not include extra pairs, but we can delete anything irrelevant.
I like solution with map/grep for the first case suggested by runrig.

But - what about range restrictions? Could somebody suggest nice-looking snippet? I could not yet :(

-- brother ab

In reply to RE: RE: Mapping restrictions by brother ab
in thread Mapping restrictions by brother ab

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