Re: String Newline Question

In a regex, $ does not mean "end of string". It means "end of line", which is just before \n or the end of the string (whichever comes first). If you want to match the null string at the end of the string, use \z.

$_ = "foo\n";
/^foo$/;    # true
/^foo\z/;   # false
/^foo\n$/;  # true
/^foo\n\z/; # true
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$ behaves like (?=\z|\n).

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Comment on Re: String Newline Question Download Code

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•Re: Re: String Newline Question by merlyn (Sage) on Mar 23, 2002 at 22:26 UTC
$ behaves like `(?=\z\|\n)` No, it behaves like `(?=\n?\z)`. Yours would match any embedded newline. -- Randal L. Schwartz, Perl hacker	[reply]
Re: •Re: Re: String Newline Question by Juerd (Abbot) on Mar 23, 2002 at 22:30 UTC
No, it behaves like (?=\n?\z). Yours would match any embedded newline. Oops, I was describing the situation for when `/m` (or `(?m:)`) is in effect, which was not the case. Update - Hm, even if that were the case, it would be wrong. It would behave like `(?=\n\z?\|\z)`. U28geW91IGNhbiBhbGwgcm90MTMgY W5kIHBhY2soKS4gQnV0IGRvIHlvdS ByZWNvZ25pc2UgQmFzZTY0IHdoZW4 geW91IHNlZSBpdD8gIC0tIEp1ZXJk	[reply]