Encoding Booleans in Featherweight Generic Go

not.fgg

package main;

type Any(type) interface { };

type Name(type a Any()) interface {
	value(type)() a
};

type Value(type a Any()) struct {
	value a
};

func (this Value(type a Any())) value(type)() a {
	return this.value
};

type Boolean(type) interface {
	iff(type a Any())(t Name(a), f Name(a)) a
};

type True(type) struct { };
func (this True(type)) iff(type a Any())(t Name(a), f Name(a)) a { return t.value()() };

type False(type) struct { };
func (this False(type)) iff(type a Any())(t Name(a), f Name(a)) a { return f.value()() };

type Example(type) struct { };
func (this Example(type)) not(type)(b Boolean(type)) Boolean(type) {
	return b.iff(Boolean())(Value(Boolean()){False(){}}, Value(Boolean()){True(){}})
};

func main() {
	_ = Example(){}.not()(True(){})
}