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

Sorry, I still don't get it.

Obviously /\z/ matches the string "f\n", so why should it fail to match if I prepend it with something that matches the empty string? This should be independent of where the end of the string is considered to be.

And why does /.?\z/ match and /.*\z/ not?

If we expand that scheme, why does /.?.?\z/ match, and /.*.?\z/ not?

In all cases I'd expect .? and .* to be reduced to the empty string - why doesn't it happen?

Comment on 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 15:47 UTC
Now I'm confused as well, my mental model doesn't seem to fit (at least not everywhere :-) Maybe demerphq could tell? --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]
Re^6: Strange regex to test for newlines: /.*\z/ by demerphq (Chancellor) on May 21, 2007 at 23:42 UTC
avar confirms this bug still exists in blead, so ill give it a look when i get a chance. right cant say more right now as i injured my arm today and hacking one handed is no fun. (yes im fine, or so the xrays said) --- $world=~s/war/peace/g	[reply]
Re^7: Strange regex to test for newlines: /.*\z/ by tinita (Parson) on May 22, 2007 at 08:20 UTC
as i injured my arm today and hacking one handed is no fun oh, then get well soon. i have a special keyboard for one-handed hackers that i could borrow you if you like ;-)	[reply]
Re^8: Strange regex to test for newlines: /.*\z/ by demerphq (Chancellor) on May 23, 2007 at 21:34 UTC


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