With Perl/PCRE matching semantics with alternation, I always think of it in terms of preference, and therefore as a feature (perhaps of dubious worth). It is p

With Perl/PCRE matching semantics with alternation, I always think of it in terms of preference, and therefore as a feature (perhaps of dubious worth). It is possible to support these semantics with an automata-based engine (see RE2; and pity junyer isn’t here to read this article, he loved derivatives), but I can’t say I recommend it. The benefit, of course, is then you can peg your test suite to PCRE.