It matches and captures at least one character and as any as it can up to (but not including) the last underscore in a string. It fails if there is not an underscore in the string and if there is not at least one character before and after the underscore.

DWIM is Perl's answer to Gödel

In reply to Re: What this pattern matches by GrandFather
in thread What this pattern matches by Anonymous Monk

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