Section GLOBALENV_PRINCIPLES.
Variable P: t -> Prop.
Remark in_norepet_unique:
forall id g (gl: list (ident * globdef F V)),
In (id, g) gl -> list_norepet (map fst gl) ->
exists gl1 gl2, gl = gl1 ++ (id, g) :: gl2 /\ ~In id (map fst gl2).
End GLOBALENV_PRINCIPLES.
(** ** Properties of the operations over global environments *)

Theorem find_invert_symbol:
forall ge id b,
find_symbol ge id = Some b -> invert_symbol ge b = Some id.