proposition: Lemma tarski_gfp_fixed (f : T -> T) : monotone f -> f (tarski_gfp f) = tarski_gfp f.
proof: Proof. move=>M; suff L: tarski_gfp f <== f (tarski_gfp f). - by apply: poset_asym=>//; apply: supP; apply: M L. by apply: supM=>x L; apply: poset_trans (L) _; apply: M; apply: supP. Qed.
imports: mathcomp(ssreflect ssrbool ssrfun ssrnat eqtype seq) pcm(options axioms pred prelude)