Re^4: Strange regex to test for newlines: /.*\z/

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Re^5: Strange regex to test for newlines: /.*\z/ by shmem (Chancellor) on May 21, 2007 at 15:44 UTC
`"\n" =~ /\n.\z/; # matches` [download] Obvious, I think. You match a "\n", then EOS (end of string). `"\n" =~ /.\z/; # doesn't match. i would expect it to match` [download] `perl -D512` tells `anchored(MBOL)` (i.e. multiline beginning of line, see perldebguts) with that one, which anchoring doesn't happen with `"\n" =~ /[^\n]\z/; # matches. like expected. but [\n] is like .*` [download] but why? `"\n" =~ /.?\z/;` [download] matches, as does `"\n" =~ /.{0,}\z/;` [download] I can't get a mental model of why the previous one should, but the next one should not match: `"f\n" =~ /.?f\z/;` [download] Weird. Rather inconsistent, if not buggy. --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l] [select]
Re^6: Strange regex to test for newlines: /.*\z/ by betterworld (Curate) on May 22, 2007 at 00:46 UTC
`"\n" =~ /\n.\z/; # matches` [download] Obvious, I think. If this one is obvious, then the original one should be obvious too. Compare: `"\n" =~ /\n.\z/; # matches "\n" =~ /.\z/; # should match but doesn't` [download] The pattern gets shorter*, but doesn't match any more...	[reply] [d/l] [select]