What Is Good About Haskell?(doisinkidney.com)

    leaf = object()

    def merge(lhs, rhs):
        if lhs is leaf: return rhs
        if rhs is leaf: return lhs
        if lhs[0] <= rhs[0]: return lhs[0], merge(rhs, lhs[2]), lhs[1]
        return rhs[0], merge(lhs, rhs[2]), rhs[1]

    def insert(tree, elt): return merge(tree, (elt, leaf, leaf))

    def popMin(tree):
        if tree is leaf: raise IndexError("popMin from leaf")
        return tree[0], merge(tree[1], tree[2])

    def listToHeap(elts):
        rv = leaf
        for elt in elts:
            rv = insert(rv, elt)
        return rv

    def listToHeap(elts): return reduce(insert, elts, leaf)

    def heapToList(tree):
        rv = []
        while tree is not leaf:
            datum, tree = popMin(tree)
            rv.append(datum)
        return rv

    enum Tree<A> {
        Leaf(A),
        Node(A, Box<Tree<A>>, Box<Tree<A>>),
    }

    @dataclass
    def Node:
        data: "Any"

    @dataclass
    def Tree(Node):
        left:  Node
        right: Node

    data,*subnodes = myTree
    for node in subnodes:
       # etc