Re: Count number of lines in a STRING

Assuming lines are defined as sequences of non-newline characters terminated by newlines, it's just a matter of counting the number of newlines. Use the tr/// operator for that.

my $nr_of_lines = $str =~ tr/\n//;
[download]

Add 1 if you want to count an incomplete last line, and the string doesn't end with a newline.

Comment on Re: Count number of lines in a STRING Select or Download Code

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Re^2: Count number of lines in a STRING by LanX (Saint) on May 12, 2010 at 09:57 UTC
> Add 1 if you want to count an incomplete last line, and the string doesn't end with a newline. better use scalar split, counting the delimiter is unnecessary complexity. `DB<1> $a="1\n2\n3";$b=$a."\n" DB<2> print scalar split /\n/ for $a,$b 33 DB<3> print scalar tr/\n// for $a,$b 23` [download] Cheers Rolf	[reply] [d/l]
Re^3: Count number of lines in a STRING by JavaFan (Canon) on May 12, 2010 at 10:10 UTC
Two problems with scalar split: 1) pre-5.12, it will globber @_. 2) it's incorrect: `print scalar split /\n/ for "1\n2\n3\n\n"; # Prints 3 instead of 4` [download] Using a negative third argument doesn't solve the problem: `print scalar split /\n/, $_, -1 for "1\n2\n3\n\n"; # Prints 5` [download] you'd have to subtract 1, but only if the string ends in a new line - so you end up looking at the end as well. As for the complexity: `print tr/\n// + !/\n\z/;` [download] even gives the correct results in list context.	[reply] [d/l] [select]
Re^4: Count number of lines in a STRING by LanX (Saint) on May 12, 2010 at 10:48 UTC
thanks didn't expect that: By default, empty leading fields are preserved, and empty trailing ones are deleted. Cheers Rolf	[reply]
Re^2: Count number of lines in a STRING by danj35 (Sexton) on May 12, 2010 at 09:45 UTC
Thanks, that's a nice neat bit of working code with the brackets added. Thanks a lot.	[reply]