Unlike pretty much any other function that returns 'false' in Perl, meaning 0 or a negative number of undef, the index() function returns the '-1' string rather than the actual number -1.

Yes, and that's to avoid the semipredicate problem. (Without warnings enabled, evaluate undef + 0 and see what you get.)

I have no idea what your title means though; it's just wrong.

In reply to Re: Perl index() Function Returns String, Not Numeric by chromatic
in thread Perl index() Function Returns String, Not Numeric by ironmo

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