in reply to Re: Mini-Tutorial: Working with Odd/Even Elements
in thread Mini-Tutorial: Working with Odd/Even Elements

  local(*{$caller."::a"}) = \my $a;
  local(*{$caller."::b"}) = \my $b;

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Does this technique depend on the default "automatic declaration" of $a and $b as package-vars? (it's meant for sort {...})

In other words: using $c for map_triples wouldn't be as easy..(?)

Cheers Rolf

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Re^3: Mini-Tutorial: Working with Odd/Even Elements
by duelafn (Parson) on Jul 10, 2009 at 11:16 UTC

    It will be a problem if you are running under strict. However, if the caller sets up $c as a package variable it will work.

    sub map_triples(&@) {
  my $f = shift;
  my @res;

  no strict 'refs';
  my $caller = caller;
  local(*{$caller."::a"}) = \my $a;
  local(*{$caller."::b"}) = \my $b;
  local(*{$caller."::c"}) = \my $c;

  push @res, $f->($a,$b,$c) while ($a, $b, $c) = splice @_, 0, 3;
  return @res;
}

use 5.010;
use warnings;
use strict;
our $c;

say for map_triples { $a + $b + $c } 1..12;

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    Good Day,
        Dean

[reply]
[d/l]
      hmm .. maybe an approach using the @_-Array (i.e. $_[0] instead $a and so on) is more scalable...

      Cheers Rolf

[reply]
[d/l]

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