in reply to Re: Count number of lines in a STRING
in thread Count number of lines in a STRING

> 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

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Cheers Rolf

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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.
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