Section int.
Variable X:Type.
Context {HX : registered X}.
Global Instance term_option_eqb : computableTime' (@option_eqb X)
(fun eqb eqbT => (1, fun a _ => (1,fun b _ => (match a,b with
Some a, Some b => callTime2 eqbT a b + 10
| _,_ => 8 end,tt)))). cbn.
Global Instance eqbComp_Option `{H:eqbCompT X (R:=HX)}:
eqbCompT (option X).
End int.
Definition isSome {T} (u : option T) := match u with Some _ => true | _ => false end.
Instance term_isSome {T} `{registered T} : computable (@isSome T).

Lemma size_option X `{registered X} (l:option X):
size (enc l) = match l with Some x => size (enc x) + 5 | _ => 3 end.