But you can't be sure that $x starts and ends with an alphanumeric character, in which case \b$x\b wouldn't match when $x is surrounded by spaces.
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re^2: regexp help -- word boundaries by japhy
in thread regexp help -- word boundaries by water

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