use Perl

• boolean test (Score:2)

  by jmm (276) <johnNO@SPAMperlwolf.com> on 2006.02.06 11:05 (#46027) Journal

  My vote for the meaning of sort in scalar context is to return whether the list was already sorted.

  unless( sort @list ) {
      # @list is not sorted, deal with it...
      ...
  }

  If you want to go beyond a simple boolean, the index of the first out of order element sounds a lot more useful than the proprtion of sorted neighbours - and, like the boolean result, it can short circuit the scan of the list as soon as an out of order pair is found.

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  • Re:boolean test (Score:1)

    by n1vux (1492)

    to return whether the list was already sorted

    An is_sorted @list predicate would be an interesting builtin/XS/Inline function, and should run faster than sort (if coded equally well). It should run about the same speed as a least @list sort-variant optimized to return (sort @_)[0].

    However, I'm not sure is_sorted should be called scalar sort, that doesn't seem any better than calling least as scalar sort. Changing sort from verb-transitive to verb-predicate when going from list to scalar context is rather

    --
    Bill
    # I had a sig when sigs were cool
    use Sig;