Scheme expr_ind2 := Induction for Csyntax.expr Sort Prop
  with exprlist_ind2 := Induction for Csyntax.exprlist Sort Prop.Combined Scheme expr_exprlist_ind from expr_ind2, exprlist_ind2.

Lemma transl_if_meets_spec: forall r s1 s2 g s g' I, transl_if r s1 s2 g = Res s g' I -> tr_if r s1 s2 s.