public void SecondFunctorLawHoldsForSelectNode(IRoseTree <int, string> t)
{
char f(bool b) => b ? 'T' : 'F';
bool g(int i) => i % 2 == 0;
Assert.Equal(
t.SelectNode(x => f(g(x))),
t.SelectNode(g).SelectNode(f));
}
public void ConsistencyLawHolds(IRoseTree <int, string> t)
{
DateTime f(int i) => new DateTime(i);
bool g(string s) => string.IsNullOrWhiteSpace(s);
Assert.Equal(t.SelectBoth(f, g), t.SelectLeaf(g).SelectNode(f));
Assert.Equal(
t.SelectNode(f).SelectLeaf(g),
t.SelectLeaf(g).SelectNode(f));
}
public void SelectNodeObeysFirstFunctorLaw(IRoseTree <int, string> t)
{
Assert.Equal(t, t.SelectNode(Id));
}