tree.jl

type Node
    label::String
    height::Float64
    parent::Node
    left::Node
    right::Node
end

Node(label::String, height::Float64) = Node(label, height, None, None, None)

type Tree
   root::Node
   origin::Float64
end

isroot(node::Node) = node.parent == None

isleaf(node::Node) = node.left == None

function preorder(node::Node)
    produce(node)
    if !isleaf(node)
        for n in Task(preorder(n.left))
            produce(n)
        end
        for n in Task(preorder(n.right))
            produce(n)
        end
    end
end

postorder(tree::Tree) = postorder(tree.root)

postorder(tree::Tree) = postorder(tree.root)

function newick(node::Node)
    if isleaf(node)
        node.label
    else
        "(" * newick(node.left) *  "," * newick(node.right) * ")"
    end *
    ":" * string(if isroot(node) 0 else node.parent.height - node.height end)
end

function newick(tree::Tree)
    newick(tree.root) * ":" * string(tree.origin - node.root.height) * ";"
end