Some definitions of interest.
hfun	Def 'a  'b == 'a'b
	Thm* 'a,'b:S. ('a  'b)  S
nat	Def  == {i:| 0i }
	Thm*   Type
	Thm*   S
ncompose	Def ncompose(f;n;x) == if n=0 then x else f(ncompose(f;n-1;x)) fi   (recursive)
	Thm* 'a:Type, n:, x:'a, f:('a'a). ncompose(f;n;x)  'a
stype	Def S == {T:Type| x:T. True }
	Thm* S  Type{2}

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