use Perl

• I think they call this a "natural sort" (Score:2)

  by bart (450)

  See Sort::Naturally [cpan.org].
  
  Your idea to use

  split /(\d+)/

  was IMHO an inspired one, so I cannot improve on that idea. Do note that the numeric string sections will always be at the list items with odd index (1, 3, 5, ...) and the string parts at even index (0, 2, 4, ...).
  
  Here's an alternative implementation, IMO somewhat streamlined, and using an OR-cache (AKA an "Orcish Manoeuvre") to store the split array:

  my %orcache;
  sub macsort {
     my $A = $orcache{$a} ||= [ split /(\d+)/, $a ];
     my $B =
  • Re: (Score:1)

    by ChrisDolan (2855)

    Nice implementation. I think the last line is better written as:

    return @$A <=> @$B;

    but since one of them must be zero, the results are equivalent.
    
    Is i & 1 preferable to i % 1? I consider the latter to be slightly more intuitive.
    
    BTW you forgot to chomp the data
    
    Yeah, I skipped that just for simplicity of the example It doesn't affect the test case.
    • Re: (Score:2)

      by bart (450)

      I think the last line is better written as:

      return @$A <=> @$B;

      Uh, of course, that's what I planned to write. I had been messing with the implementation showing debugging information during the comparison, and this must be a leftover. That's my story and I'm sticking to it. ;-)

      Is i & 1 preferable to i % 1? I consider the latter to be slightly more intuitive.

      At least it gives the correct results. :-) Surely you ment to type $i % 2.

      A recent thread on Perlmonks [perlmonks.org] by diotalevi shows that nowadays, these instructions take the same time. It used to make a difference, in my favour, 20 years ago before the numerical coprocessors, that all CPUs have
      • Re: (Score:1)

        by ChrisDolan (2855)

        Is i & 1 preferable to i % 1? I consider the latter to be slightly more intuitive.

        At least it gives the correct results. :-) Surely you ment to type $i % 2.

        Uh, of course, that's what I planned to write. That's my story and I'm sticking to it. :-P