public void SecondFunctorLawHoldsForSelectRight(IEither <string, int> e)
{
char f(bool b) => b ? 'T' : 'F';
bool g(int i) => i % 2 == 0;
Assert.Equal(
e.SelectRight(x => f(g(x))),
e.SelectRight(g).SelectRight(f));
}
public void ConsistencyLawHolds(IEither <string, int> e)
{
bool f(string s) => string.IsNullOrWhiteSpace(s);
DateTime g(int i) => new DateTime(i);
Assert.Equal(e.SelectBoth(f, g), e.SelectRight(g).SelectLeft(f));
Assert.Equal(
e.SelectLeft(f).SelectRight(g),
e.SelectRight(g).SelectLeft(f));
}
// Functor
public static IEither <L, R1> Select <L, R, R1>(
this IEither <L, R> source,
Func <R, R1> selector)
{
return(source.SelectRight(selector));
}
public void SelectRightObeysFirstFunctorLaw(IEither <string, int> e)
{
Assert.Equal(e, e.SelectRight(Id));
}