Some definitions of interest.
his_num_rep	Def is_num_rep Def == m:. P: Def == m:. ((P(zero_rep))(n:. (P(n))(P(suc_rep(n)))))(P(m))
	Thm* is_num_rep  (hind  hbool)
assert	Def b == if b True else False fi
	Thm* b:. b  Prop
hrep_num	Def rep_num == n:. ncompose(suc_rep;n;zero_rep)
	Thm* rep_num  (hnum  hind)
nat	Def  == {i:| 0i }
	Thm*   Type
	Thm*   S

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