Well, 10 out of 10 for cleverness, but abigail's trick only removes empty lines, i.e. those that match /^$/; but the original requirement was to remove lines made up of any combination of whitespace.

    -- Chip Salzenberg, Free-Floating Agent of Chaos

In reply to Re: Re: One-liner removes whitespace-only lines from text file by chip
in thread (code) One-liner removes whitespace-only lines from text file by ybiC

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