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does /xyz$/ match "xyz\n" in pcre& #39;s multi-line mode? yes. Does it match also in not multi-line mode? also yes. *because there& #39;s a special case for \n at the end of the string.* 
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if you don& #39;t understand why this is confusing... pcre goes through several layers of irony when deciding whether to match something or not
I& #39;m dealing with this by having the AST constructed with [\n]?$ for the anchored predicate, so our basic dumb NFA now looks like this. What a mess. (The unused .* at each end are attachment points for the unanchored forms - those get trimmed away during conversion to DFA, later)
![I& #39;m dealing with this by having the AST constructed with [\n]?$ for the anchored predicate, so our basic dumb NFA now looks like this. What a mess. (The unused .* at each end are attachment points for the unanchored forms - those get trimmed away during conversion to DFA, later)](https://pbs.twimg.com/media/Eyj7-vpUcAMHwTA.jpg "I& #39;m dealing with this by having the AST constructed with [\n]?$ for the anchored predicate, so our basic dumb NFA now looks like this. What a mess. (The unused .* at each end are attachment points for the unanchored forms - those get trimmed away during conversion to DFA, later)")
I& #39;m annoyed because now I have to update all my tests for the NFA construction to expect the optional newline there.
