Thm* Alph,States:Type, n:NDA(Alph;States). I(n) States

Def hd(l) == Case of l; nil "?" ; h.t h

Thm* A:Type, l:A*. ||l||1 hd(l) A

Def NDA(Alph;States) == (StatesAlphStatesProp)States(States)

Thm* Alph,States:Type{i}. nd_automata{i}(Alph;States) Type{i'}

Thm* A:Type, B:(AType), p:a:AB(a). 1of(p) A

Def rev(as) == Case of as; nil nil ; a.as' rev(as') @ [a] (recursive)

Thm* T:Type, as:T*. rev(as) T*

Thm* A:Type, B:(AType), p:a:AB(a). 2of(p) B(1of(p))

Def as @ bs == Case of as; nil bs ; a.as' a.(as' @ bs) (recursive)

Thm* T:Type, as,bs:T*. (as @ bs) T*