public static TMonad When <TMonad>(bool b, TMonad m)
where TMonad : IMonad <Unit>
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return((TMonad)(b ? m : monadAdapter.Return(new Unit())));
}
public void Test1()
{
var eitherMonadAdapter = MonadAdapterRegistry.Get <string>(typeof(Either <,>));
var either = (Either <string, int>)eitherMonadAdapter.Return(42);
Assert.That(either.Right, Is.EqualTo(42));
}
public static Func <TA, TMonad> Compose <TMonad, TA, TB, TC>(Func <TA, IMonad <TB> > f, Func <TB, IMonad <TC> > g)
where TMonad : IMonad <TC>
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return(a => (TMonad)monadAdapter.Bind(f(a), g));
}
// ReSharper disable FunctionRecursiveOnAllPaths
public static TMonad Forever <TMonad, TA, TB>(IMonad <TA> m)
where TMonad : IMonad <TB>
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return((TMonad)monadAdapter.BindIgnoringLeft(m, Forever <TMonad, TA, TB>(m)));
}
// ReSharper restore FunctionRecursiveOnAllPaths
public static TMonad Void <TMonad, TA>(IMonad <TA> m)
where TMonad : IMonad <Unit>
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return((TMonad)monadAdapter.BindIgnoringLeft(m, monadAdapter.Return(new Unit())));
}
public void Test3()
{
var writerMonadAdapter = MonadAdapterRegistry.Get <ListMonoid <TwTuple>, TwTuple>(typeof(Writer <ListMonoid <TwTuple>, TwTuple, int>));
var writer = (Writer <ListMonoid <TwTuple>, TwTuple, int>)writerMonadAdapter.Return(42);
Assert.That(writer.RunWriter.Item1, Is.EqualTo(42));
}
public static TMonad Join <TMonadMonad, TMonad, TA>(TMonadMonad mma)
where TMonadMonad : IMonad <TMonad>
where TMonad : IMonad <TA>
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return((TMonad)monadAdapter.Bind(mma, ma => ma));
}
// ReSharper disable InconsistentNaming
public static TMonad FoldM_ <TMonad, TA, TB>(Func <TA, TB, IMonad <TA> > f, TA a, IEnumerable <TB> bs)
where TMonad : IMonad <Unit>
// ReSharper restore InconsistentNaming
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return((TMonad)monadAdapter.BindIgnoringLeft(FoldM <IMonad <TA>, TA, TB>(f, a, bs), monadAdapter.Return(new Unit())));
}
// ReSharper disable InconsistentNaming
public static TMonad Sequence_ <TMonad, TA>(IEnumerable <IMonad <TA> > ms)
where TMonad : IMonad <Unit>
// ReSharper restore InconsistentNaming
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
var z = monadAdapter.Return(new Unit());
return((TMonad)ms.FoldRight(z, monadAdapter.BindIgnoringLeft));
}
public static TMonad Sequence <TMonad, TA>(IEnumerable <IMonad <TA> > ms)
where TMonad : IMonad <IEnumerable <TA> >
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
var z = monadAdapter.Return(MonadHelpers.Nil <TA>());
return((TMonad)ms.FoldRight(
z, (m, mtick) => monadAdapter.Bind(
m, x => monadAdapter.Bind(
mtick, xs => monadAdapter.Return(MonadHelpers.Cons(x, xs))))));
}
public static TMonad FoldM <TMonad, TA, TB>(Func <TA, TB, IMonad <TA> > f, TA a, IEnumerable <TB> bs)
where TMonad : IMonad <TA>
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return((TMonad)bs.HeadAndTail().Match(
tuple =>
{
var x = tuple.Item1;
var xs = tuple.Item2;
var m = f(a, x);
return monadAdapter.Bind(m, acc => FoldM <TMonad, TA, TB>(f, acc, xs));
},
() => monadAdapter.Return(a)));
}
public static TMonad FilterM <TMonad, TA>(Func <TA, IMonad <bool> > p, IEnumerable <TA> @as)
where TMonad : IMonad <IEnumerable <TA> >
{
var monadAdapter = MonadAdapterRegistry.Get(typeof(TMonad));
return((TMonad)@as.HeadAndTail().Match(
tuple =>
{
var x = tuple.Item1;
var xs = tuple.Item2;
return monadAdapter.Bind(
p(x), flg => monadAdapter.Bind(
FilterM <TMonad, TA>(p, xs),
ys => monadAdapter.Return(flg ? MonadHelpers.Cons(x, ys) : ys)));
},
() => monadAdapter.Return(MonadHelpers.Nil <TA>())));
}
public MonadAdapter <TLeft> GetMonadAdapter()
{
return(MonadAdapterRegistry.Get <TLeft>(typeof(Either <,>)));
}
public MonadAdapter <TR> GetMonadAdapter()
{
return(MonadAdapterRegistry.Get <TR>(typeof(Reader <,>)));
}
public MonadAdapter <TMonoid, TW> GetMonadAdapter()
{
return(MonadAdapterRegistry.Get <TMonoid, TW>(typeof(Writer <, ,>)));
}
public MonadAdapter <TS> GetMonadAdapter()
{
return(MonadAdapterRegistry.Get <TS>(typeof(State <,>)));
}
public MonadAdapter GetMonadAdapter()
{
return(MonadAdapterRegistry.Get(typeof(Maybe <>)));
}
