20 lines
524 B
Coq
20 lines
524 B
Coq
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Require Import base.
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Class Policy (action domain : Type) := {
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dom : action -> domain;
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domain_dec :> forall (x y : domain), Decision (x = y);
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policy :> relation domain;
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policy_dec :> (forall v w, Decision (policy v w));
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policy_refl :> Reflexive policy
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}.
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Infix "⇝" := policy (at level 70).
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Fixpoint purge `{Policy action domain} (ls : list action) (v : domain) : list action :=
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match ls with
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else purge tl v
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end.
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