Is there an n-ary tree implementation in Perl?

I'm writing a Perl script and would like to use a n-ary tree data structure.

Is there a good implementation that is available as source code (rather than part of a Perl library) ?

From stackoverflow David

• I don't really understand why you want it was "source" rather than as a perl library, but you can download the source for any CPAN module.

  I haven't used it, but Tree looks to fill your requirements.

  From Matthew Watson

• Adding to what Matthew already said, it looks like the following modules would be suitable:

  Tree::Nary
  Tree::Simple
  Tree

  From ChrisN

• Depending on what you need a tree structure for, you might not need any pre-built implementation. Perl already supports them using arrays of arrayrefs.

  For example, a simple representation of this tree

               t
             /   \
            a     d
           / \   / \
          b   c e   f
  

  could be represented by the following Perl code:

  $tree = [ t => [ a => [ b => [], c => [] ]
                   d => [ e => [], f => [] ] ] ];
  

  Here, the tree's representation is as nested pairs: first the element (in this case, the letter), then an anonymous array reference representing the children of that element. Note that => is just a fancy comma in Perl that exempts you having to put quotes around the the token to the left of the comma, provided it is a single word. The above code could also have been written thus:

  $tree = [ 't', [ 'a' , [ 'b' , [], 'c' , [] ]
                   'd' , [ 'e' , [], 'f' , [] ] ] ];
  

  Here's a simple depth-first accumulator of all the elements in the tree:

  sub elements {
      my $tree = shift;
  
      my @elements;
      my @queue = @$tree;
      while (@queue) {
          my $element  = shift @queue;
          my $children = shift @queue;
          push @elements, $element;
          unshift @queue, @$children;
      }
  
      return @elements;
  }
  
  @elements = elements($tree)     # qw(t a b c d e f)
  

  (For breadth first, change the line unshift @queue, @$children to push @queue, @$children)

  So, depending on what operations you want to perform on your tree, the simplest thing might be just to use Perl's built-in support for arrays and array references.

  From nohat