public IMonad <A> Where(Func <A, int, bool> predicate)
{
Maybe <A> result = new Nothing <A>();
if (!this.isNothing && predicate(aValue, 0))
{
result = new Just <A>(aValue);
}
return(result);
}
/// <summary>
/// If this is not nothing, then the result monad is a new Maybe<A> with the value inside the other monad.
/// </summary>
/// <param name="otherMonad">The other monad.</param>
/// <returns>The new monad.</returns>
public IMonad <A> Concat(IMonad <A> otherMonad)
{
Maybe <A> resultMonad = new Nothing <A>();
if (!isNothing)
{
resultMonad = new Just <A>(otherMonad.Return());
}
return(resultMonad);
}
public IMonad <C> Com <B, C>(Func <A, B, C> function, IMonad <B> mOther)
{
IMonad <C> resultMonad = new Nothing <C>(); // New Nothing<B> maybe
if (!isNothing && !(mOther is Nothing <B>))
{
foreach (var otherValue in mOther)
{
resultMonad = new Just <C>(function(aValue, otherValue));
}
}
return(resultMonad);
}
public IMonad <B> App <B>(IMonad <Func <A, B> > functionMonad)
{
Maybe <B> result = new Nothing <B>();
if (this is Just <A> && functionMonad != null)
{
foreach (var function in functionMonad)
{
if (function != null)
{
result = new Just <B>(functionMonad.Return()(aValue));
}
}
if (result == null)
{
result = new Nothing <B>();
}
}
return(result);
}