tr/ /_/s;, as /s is for squash multiple.

Doing it in one line while removing leading whitespace is trickier. There are several potentially nasty regular expressions. Just say no.

Update: Squashing several expressions onto one line technically counts, but it wasn't what I meant, smart guy!

In reply to Re: Replacing multiple spaces into one character? by chromatic
in thread Replacing multiple spaces into one character? by r.joseph

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