Support library for working with tree data structures.

A tree is represented by a compound term with the following components:

• Label :: A (compound) term that describes the relationship between the Parent node and the Children subtrees.
• Parent :: A (compound) term that represents the parent node.
• Children :: A list of trees. Empty if Parent is a leaf node.

Here are some examples of tree terms:

tree(leaf, 'Electra', [])

tree(father,
     'Agamemnon',
     [tree(leaf, 'Electra', []),
      tree(leaf, 'Orestes', [])])

tree('Modus ponens',
     'Socrates is mortal',
     [tree(premise, 'Sorcrates is a man', []),
      tree(premise, 'Men are mortal', [])])

author

- Wouter Beek

version

- 2021-03-18

 depth(+Tree:compound, +Depth:nonneg) is semidet

depth(+Tree:compound, -Depth:nonneg) is det

Succeeds for the Depth of the Tree.

The depth of a tree is defined inductively:

• 0 for leaf nodes.
• 1 plus the maxium of the depth of the children.

 shortest(+Trees:list(compound), +Tree:compound) is semidet

shortest(+Trees:list(compound), -Tree:compound) is det

Succeeds if Tree is the shotests of Trees.