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(* Lemmas for instantiating ghost variables *)
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Variables (s : C -> spec A) (f : DTbin this W (logvar s)).

(* Instantiating the ghost of a call *)
Lemma gh_ex g i (k : cont A) :
verify i (do' (@gh_conseq g)) k ->
verify i (@with_spec this W A (logvar s) f) k.