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in reply to Reporting

my $num_elements = @array; is not the same as my $num_elements = $#array; The second will give you one less than the length because it actually returns the index of the last element.

kelan

Perl6 Grammar Student

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Re: Re: Reporting
by dragonchild (Archbishop) on Apr 03, 2003 at 19:10 UTC
    I think the question was more of which of the following is faster: 
    if ($#array >= 0)

### or ...

if (@array > 0)

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[d/l]

      Both of those are better written as if (@array) {. Its likely to be less ops as well.

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[d/l]
      Im actually thinking the question was.

      Which is faster? 
      $num = scalar(@array);
# or 
$num = $#array;

      [download]
      And as someone pointed out $#array isnt acurate as to the actual number of elements in the array, so I guess you could simply compare the op trees of the two. Or I guess perform 3 benchmarks,
      1) plain
      2) scalar(@array) - 1
      3) $#array + 1;

      /* And the Creator, against his better judgement, wrote man.c */
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[d/l]

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