Weight.Weight_as_DepthSourceA module that implements weight as the depth of a tree (the number of nodes does not matter. The smaller, the better
The type of weight
pp fmt w pretty prints the weight w on the formatter fmt.
is better w1 w2 returns true if w1 is strictly better (in the sense implemented by the module) than w2
up w v returns the new weight computed from w and from v (the label of the current node, before moving up in the tree).
down w v returns the new weight computed from w and from v (the label of the current node, before moving down in the tree).
right w v returns the new weight computed from w and from v (the label parent node of the current node.