What's a good way to write the regular expression so that perl will start searching from the end of the string?

That's what end anchors ($, \z, \Z) are for... And if you only need to do a simple substring search, you can also use rindex().

In reply to Re: Optimizing a regex that replaces near the end of a string by almut
in thread Optimizing a regex that replaces near the end of a string by perl5ever

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