public static bool unify(Dictionary <Monomorphic, Monomorphic> m, Monomorphic s, Monomorphic t)
{
if (s is Slot && t is Slot && s.applySub(m).Equals(t.applySub(m)))
{
return(true);
}
else if (s is Primitive && t is Primitive && ((Primitive)s).Name == ((Primitive)t).Name)
{
return(true);
}
else if (s is Composite && t is Composite)
{
var s_ = (Composite)s;
var t_ = (Composite)t;
return(unify(m, s_.Ctor, t_.Ctor) && unify(m, s_.Argument, t_.Argument));
}
else if (s is Slot)
{
m.Add(s, t);
return(true);
}
else if (t is Slot)
{
m.Add(t, s);
return(true);
}
else
{
return(false);
}
}
public Composite(Monomorphic ctor, Monomorphic argument)
{
Ctor = ctor;
Argument = argument;
}
public static Composite Arrow(Monomorphic p, Monomorphic q)
{
return(ct(ct(pm("[->]"), p), q));
}
public static Composite Product(Monomorphic p, Monomorphic q)
{
return(ct(ct(pm("[*]"), p), q));
}
public static Composite ct(Monomorphic ctor, Monomorphic argument)
{
return(new Composite(ctor, argument));
}