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theory Predicate_Compiletheory Predicate_Compile imports Complex_Main Code_Index Lattice_Syntax uses "predicate_compile.ML" begin setup {* Predicate_Compile.setup *} primrec "next" :: "('a Predicate.pred => ('a × 'a Predicate.pred) option) => 'a Predicate.seq => ('a × 'a Predicate.pred) option" where "next yield Predicate.Empty = None" | "next yield (Predicate.Insert x P) = Some (x, P)" | "next yield (Predicate.Join P xq) = (case yield P of None => next yield xq | Some (x, Q) => Some (x, Predicate.Seq (λ_. Predicate.Join Q xq)))" ML {* let fun yield (@{code Predicate.Seq} f) = @{code next} yield (f ()) in yield @{code "⊥ :: 'a Predicate.pred"} (*replace bottom with sequence to evaluate*) end *} fun anamorph :: "('b => ('a × 'b) option) => index => 'b => 'a list × 'b" where "anamorph f k x = (if k = 0 then ([], x) else case f x of None => ([], x) | Some (v, y) => let (vs, z) = anamorph f (k - 1) y in (v # vs, z))" ML {* let fun yield (@{code Predicate.Seq} f) = @{code next} yield (f ()) fun yieldn k = @{code anamorph} yield k in yieldn 0 (*replace with number of elements to retrieve*) @{code "⊥ :: 'a Predicate.pred"} (*replace bottom with sequence to evaluate*) end *} end