public static IRoseTree <N1, L1> BiMap <N, N1, L, L1>(
this IRoseTree <N, L> source,
Func <N, N1> mapNode,
Func <L, L1> mapLeaf)
=> source.Cata(
node: (n, branches) => new RoseNode <N1, L1>(mapNode(n), branches),
leaf: l => (IRoseTree <N1, L1>) new RoseLeaf <N1, L1>(mapLeaf(l))
);
// Bifunctor
public static IRoseTree <N1, L1> SelectBoth <N, N1, L, L1>(
this IRoseTree <N, L> source,
Func <N, N1> selectNode,
Func <L, L1> selectLeaf)
{
return(source.Cata(
node: (n, branches) => new RoseNode <N1, L1>(selectNode(n), branches),
leaf: l => (IRoseTree <N1, L1>) new RoseLeaf <N1, L1>(selectLeaf(l))));
}
public void CataNode()
{
IRoseTree <string, int> tree =
RoseTree.Node(
"foo",
new RoseLeaf <string, int>(42),
new RoseLeaf <string, int>(1337));
int actual = tree.Cata((x, xs) => x.Length + xs.Sum(), x => x);
Assert.Equal(1382, actual);
}
public static Maybe <L> Find <N, L>(this IRoseTree <N, L> source, Func <L, bool> f)
=> source.Cata(
node: (x, xs) => xs.ToList().Find(x => f(x)),
leaf: l => l
);
public static int CountLeaves <N, L>(this IRoseTree <N, L> source)
=> source.Cata(
node: (x, xs) => xs.ToList().FindAll(x => x == 1).Count(),
leaf: l => 1
);
public static int Max(this IRoseTree <int, int> source) => source.Cata((x, xs) => xs.Any() ? Math.Max(x, xs.Max()) : x, l => l);
public static int Sum(this IRoseTree <int, int> source) => source.Cata((x, xs) => x + xs.Sum(), l => l);
