private Class <Bind, Id, TR> Map(Sequence <IExpression <Bind, Id, Bind> > environment, IUniverse universe, Class <Bind, Id, T> @class)
{
switch (@class.Tag)
{
case Class <Bind, Id, T> .Tags.Quantifier:
var quantifier = (Class <Bind, Id, T> .Quantifier)@class;
environment = environment.Push(quantifier.Dependency);
var qualifiedDependent = universe.Qualify <Bind, Id, T>(quantifier.Dependent);
var dependent = ConvertF(qualifiedDependent.Annotate(environment));
return(new Class <Bind, Id, TR> .Quantifier(quantifier.Dependency, dependent));
case Class <Bind, Id, T> .Tags.Shift:
var shift = (Class <Bind, Id, T> .Shift)@class;
var qualifiedContent = universe.Dual().Qualify <Bind, Id, T>(shift.Content);
var content = ConvertF(qualifiedContent.Annotate(environment));
return(new Class <Bind, Id, TR> .Shift(content));
default:
throw new InvalidProgramException("Should never happen.");
}
}
private static ITerm <Id, Id> ForallType <Id>(IUniverse universe, Id identifier, Func <ITerm <Id, Id>, ITerm <Id, Id> > dependent)
{
var dependency = universe.Qualify <Id, Id, Id>(term: identifier);
var variable = new Term <Id, Id>(new TermF <Id, Id, ITerm <Id, Id> > .Variable(dependency.Term));
return(new Term <Id, Id>(new TermF <Id, Id, ITerm <Id, Id> > .Type(new Class <Id, Id, ITerm <Id, Id> > .Quantifier(dependency, dependent(variable)))));
}
private static Func <Term <Guid>, Term <Guid> > CompileDestructor(IUniverse universe, Class <Guid, Guid, ITerm <Guid, Guid> > @class, Func <Term <Guid>, Term <Guid> > focus, Continuation <Guid, Func <Term <Guid>, Term <Guid> > > continuation)
{
switch (universe.Polarity)
{
case Polarity.Forall:
{
return(arguments =>
{
var initialization = CompileNegativeDestructor(arguments, @class, continuation);
return focus(new Term <Guid> .Constructor(initialization));
});
}
case Polarity.Exists:
{
var qualifiedSelfType = universe.Qualify <Guid, Guid, ITerm <Guid, Guid> >(new Term <Guid, Guid>(new TermF <Guid, Guid, ITerm <Guid, Guid> > .Type(@class)));
var compiledSelfType = Compile(qualifiedSelfType);
var selfUniverse = new Term <Guid> .Universe(universe.Rank);
return(arguments =>
{
var qualifiedSelf = new Qualified <Guid, Term <Guid> >(selfUniverse, compiledSelfType, focus(null));
var cont = CompilePositiveDestructor(arguments, @class, continuation);
return new Term <Guid> .Destructor(qualifiedSelf, cont);
});
}
case null:
default:
throw new ArgumentOutOfRangeException("polarity");
}
}