author | haftmann |
Fri, 11 Jun 2010 17:14:02 +0200 | |
changeset 37407 | 61dd8c145da7 |
parent 36176 | 3fe7e97ccca8 |
child 37591 | d3daea901123 |
permissions | -rw-r--r-- |
26170 | 1 |
(* Title: HOL/Library/Heap_Monad.thy |
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Author: John Matthews, Galois Connections; Alexander Krauss, Lukas Bulwahn & Florian Haftmann, TU Muenchen |
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*) |
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header {* A monad with a polymorphic heap *} |
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theory Heap_Monad |
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imports Heap |
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begin |
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subsection {* The monad *} |
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subsubsection {* Monad combinators *} |
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datatype exception = Exn |
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text {* Monadic heap actions either produce values |
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and transform the heap, or fail *} |
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datatype 'a Heap = Heap "heap \<Rightarrow> ('a + exception) \<times> heap" |
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primrec |
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execute :: "'a Heap \<Rightarrow> heap \<Rightarrow> ('a + exception) \<times> heap" where |
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"execute (Heap f) = f" |
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lemmas [code del] = execute.simps |
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lemma Heap_execute [simp]: |
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"Heap (execute f) = f" by (cases f) simp_all |
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lemma Heap_eqI: |
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"(\<And>h. execute f h = execute g h) \<Longrightarrow> f = g" |
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by (cases f, cases g) (auto simp: expand_fun_eq) |
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lemma Heap_eqI': |
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"(\<And>h. (\<lambda>x. execute (f x) h) = (\<lambda>y. execute (g y) h)) \<Longrightarrow> f = g" |
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by (auto simp: expand_fun_eq intro: Heap_eqI) |
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lemma Heap_strip: "(\<And>f. PROP P f) \<equiv> (\<And>g. PROP P (Heap g))" |
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proof |
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fix g :: "heap \<Rightarrow> ('a + exception) \<times> heap" |
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assume "\<And>f. PROP P f" |
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then show "PROP P (Heap g)" . |
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next |
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fix f :: "'a Heap" |
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assume assm: "\<And>g. PROP P (Heap g)" |
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then have "PROP P (Heap (execute f))" . |
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then show "PROP P f" by simp |
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qed |
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definition |
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heap :: "(heap \<Rightarrow> 'a \<times> heap) \<Rightarrow> 'a Heap" where |
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[code del]: "heap f = Heap (\<lambda>h. apfst Inl (f h))" |
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lemma execute_heap [simp]: |
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"execute (heap f) h = apfst Inl (f h)" |
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by (simp add: heap_def) |
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definition |
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bindM :: "'a Heap \<Rightarrow> ('a \<Rightarrow> 'b Heap) \<Rightarrow> 'b Heap" (infixl ">>=" 54) where |
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[code del]: "f >>= g = Heap (\<lambda>h. case execute f h of |
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(Inl x, h') \<Rightarrow> execute (g x) h' |
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| r \<Rightarrow> r)" |
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notation |
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bindM (infixl "\<guillemotright>=" 54) |
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abbreviation |
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chainM :: "'a Heap \<Rightarrow> 'b Heap \<Rightarrow> 'b Heap" (infixl ">>" 54) where |
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"f >> g \<equiv> f >>= (\<lambda>_. g)" |
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notation |
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chainM (infixl "\<guillemotright>" 54) |
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definition |
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return :: "'a \<Rightarrow> 'a Heap" where |
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[code del]: "return x = heap (Pair x)" |
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lemma execute_return [simp]: |
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"execute (return x) h = apfst Inl (x, h)" |
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by (simp add: return_def) |
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definition |
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raise :: "string \<Rightarrow> 'a Heap" where -- {* the string is just decoration *} |
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[code del]: "raise s = Heap (Pair (Inr Exn))" |
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lemma execute_raise [simp]: |
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"execute (raise s) h = (Inr Exn, h)" |
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by (simp add: raise_def) |
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subsubsection {* do-syntax *} |
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text {* |
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We provide a convenient do-notation for monadic expressions |
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well-known from Haskell. @{const Let} is printed |
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specially in do-expressions. |
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*} |
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nonterminals do_expr |
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syntax |
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"_do" :: "do_expr \<Rightarrow> 'a" |
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("(do (_)//done)" [12] 100) |
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"_bindM" :: "pttrn \<Rightarrow> 'a \<Rightarrow> do_expr \<Rightarrow> do_expr" |
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("_ <- _;//_" [1000, 13, 12] 12) |
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"_chainM" :: "'a \<Rightarrow> do_expr \<Rightarrow> do_expr" |
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("_;//_" [13, 12] 12) |
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"_let" :: "pttrn \<Rightarrow> 'a \<Rightarrow> do_expr \<Rightarrow> do_expr" |
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("let _ = _;//_" [1000, 13, 12] 12) |
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"_nil" :: "'a \<Rightarrow> do_expr" |
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("_" [12] 12) |
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syntax (xsymbols) |
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"_bindM" :: "pttrn \<Rightarrow> 'a \<Rightarrow> do_expr \<Rightarrow> do_expr" |
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("_ \<leftarrow> _;//_" [1000, 13, 12] 12) |
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translations |
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"_do f" => "f" |
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"_bindM x f g" => "f \<guillemotright>= (\<lambda>x. g)" |
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"_chainM f g" => "f \<guillemotright> g" |
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"_let x t f" => "CONST Let t (\<lambda>x. f)" |
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"_nil f" => "f" |
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print_translation {* |
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let |
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fun dest_abs_eta (Abs (abs as (_, ty, _))) = |
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let |
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val (v, t) = Syntax.variant_abs abs; |
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in (Free (v, ty), t) end |
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| dest_abs_eta t = |
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let |
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val (v, t) = Syntax.variant_abs ("", dummyT, t $ Bound 0); |
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in (Free (v, dummyT), t) end; |
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fun unfold_monad (Const (@{const_syntax bindM}, _) $ f $ g) = |
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let |
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val (v, g') = dest_abs_eta g; |
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val vs = fold_aterms (fn Free (v, _) => insert (op =) v | _ => I) v []; |
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val v_used = fold_aterms |
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(fn Free (w, _) => (fn s => s orelse member (op =) vs w) | _ => I) g' false; |
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in if v_used then |
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Const (@{syntax_const "_bindM"}, dummyT) $ v $ f $ unfold_monad g' |
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else |
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Const (@{syntax_const "_chainM"}, dummyT) $ f $ unfold_monad g' |
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end |
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| unfold_monad (Const (@{const_syntax chainM}, _) $ f $ g) = |
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Const (@{syntax_const "_chainM"}, dummyT) $ f $ unfold_monad g |
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| unfold_monad (Const (@{const_syntax Let}, _) $ f $ g) = |
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let |
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val (v, g') = dest_abs_eta g; |
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in Const (@{syntax_const "_let"}, dummyT) $ v $ f $ unfold_monad g' end |
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| unfold_monad (Const (@{const_syntax Pair}, _) $ f) = |
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Const (@{const_syntax return}, dummyT) $ f |
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| unfold_monad f = f; |
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fun contains_bindM (Const (@{const_syntax bindM}, _) $ _ $ _) = true |
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| contains_bindM (Const (@{const_syntax Let}, _) $ _ $ Abs (_, _, t)) = |
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contains_bindM t; |
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fun bindM_monad_tr' (f::g::ts) = list_comb |
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(Const (@{syntax_const "_do"}, dummyT) $ |
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unfold_monad (Const (@{const_syntax bindM}, dummyT) $ f $ g), ts); |
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fun Let_monad_tr' (f :: (g as Abs (_, _, g')) :: ts) = |
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if contains_bindM g' then list_comb |
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(Const (@{syntax_const "_do"}, dummyT) $ |
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unfold_monad (Const (@{const_syntax Let}, dummyT) $ f $ g), ts) |
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else raise Match; |
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in |
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[(@{const_syntax bindM}, bindM_monad_tr'), |
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(@{const_syntax Let}, Let_monad_tr')] |
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end; |
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*} |
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subsection {* Monad properties *} |
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subsubsection {* Monad laws *} |
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lemma return_bind: "return x \<guillemotright>= f = f x" |
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by (simp add: bindM_def return_def) |
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lemma bind_return: "f \<guillemotright>= return = f" |
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proof (rule Heap_eqI) |
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fix h |
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show "execute (f \<guillemotright>= return) h = execute f h" |
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by (auto simp add: bindM_def return_def split: sum.splits prod.splits) |
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qed |
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lemma bind_bind: "(f \<guillemotright>= g) \<guillemotright>= h = f \<guillemotright>= (\<lambda>x. g x \<guillemotright>= h)" |
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by (rule Heap_eqI) (auto simp add: bindM_def split: split: sum.splits prod.splits) |
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lemma bind_bind': "f \<guillemotright>= (\<lambda>x. g x \<guillemotright>= h x) = f \<guillemotright>= (\<lambda>x. g x \<guillemotright>= (\<lambda>y. return (x, y))) \<guillemotright>= (\<lambda>(x, y). h x y)" |
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by (rule Heap_eqI) (auto simp add: bindM_def split: split: sum.splits prod.splits) |
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lemma raise_bind: "raise e \<guillemotright>= f = raise e" |
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by (simp add: raise_def bindM_def) |
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lemmas monad_simp = return_bind bind_return bind_bind raise_bind |
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subsection {* Generic combinators *} |
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definition |
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liftM :: "('a \<Rightarrow> 'b) \<Rightarrow> 'a \<Rightarrow> 'b Heap" |
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where |
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"liftM f = return o f" |
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definition |
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compM :: "('a \<Rightarrow> 'b Heap) \<Rightarrow> ('b \<Rightarrow> 'c Heap) \<Rightarrow> 'a \<Rightarrow> 'c Heap" (infixl ">>==" 54) |
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where |
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"(f >>== g) = (\<lambda>x. f x \<guillemotright>= g)" |
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notation |
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compM (infixl "\<guillemotright>==" 54) |
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lemma liftM_collapse: "liftM f x = return (f x)" |
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by (simp add: liftM_def) |
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lemma liftM_compM: "liftM f \<guillemotright>== g = g o f" |
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by (auto intro: Heap_eqI' simp add: expand_fun_eq liftM_def compM_def bindM_def) |
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lemma compM_return: "f \<guillemotright>== return = f" |
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by (simp add: compM_def monad_simp) |
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lemma compM_compM: "(f \<guillemotright>== g) \<guillemotright>== h = f \<guillemotright>== (g \<guillemotright>== h)" |
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by (simp add: compM_def monad_simp) |
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lemma liftM_bind: |
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"(\<lambda>x. liftM f x \<guillemotright>= liftM g) = liftM (\<lambda>x. g (f x))" |
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by (rule Heap_eqI') (simp add: monad_simp liftM_def bindM_def) |
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lemma liftM_comp: |
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"liftM f o g = liftM (f o g)" |
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by (rule Heap_eqI') (simp add: liftM_def) |
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lemmas monad_simp' = monad_simp liftM_compM compM_return |
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compM_compM liftM_bind liftM_comp |
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primrec |
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mapM :: "('a \<Rightarrow> 'b Heap) \<Rightarrow> 'a list \<Rightarrow> 'b list Heap" |
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where |
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"mapM f [] = return []" |
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| "mapM f (x#xs) = do y \<leftarrow> f x; |
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ys \<leftarrow> mapM f xs; |
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return (y # ys) |
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done" |
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primrec |
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foldM :: "('a \<Rightarrow> 'b \<Rightarrow> 'b Heap) \<Rightarrow> 'a list \<Rightarrow> 'b \<Rightarrow> 'b Heap" |
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where |
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"foldM f [] s = return s" |
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| "foldM f (x#xs) s = f x s \<guillemotright>= foldM f xs" |
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definition |
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assert :: "('a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> 'a Heap" |
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where |
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"assert P x = (if P x then return x else raise (''assert''))" |
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lemma assert_cong [fundef_cong]: |
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assumes "P = P'" |
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assumes "\<And>x. P' x \<Longrightarrow> f x = f' x" |
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shows "(assert P x >>= f) = (assert P' x >>= f')" |
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using assms by (auto simp add: assert_def return_bind raise_bind) |
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subsubsection {* A monadic combinator for simple recursive functions *} |
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text {* Using a locale to fix arguments f and g of MREC *} |
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locale mrec = |
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fixes |
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f :: "'a => ('b + 'a) Heap" |
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and g :: "'a => 'a => 'b => 'b Heap" |
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begin |
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function (default "\<lambda>(x,h). (Inr Exn, undefined)") |
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mrec |
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where |
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"mrec x h = |
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(case Heap_Monad.execute (f x) h of |
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(Inl (Inl r), h') \<Rightarrow> (Inl r, h') |
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| (Inl (Inr s), h') \<Rightarrow> |
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(case mrec s h' of |
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(Inl z, h'') \<Rightarrow> Heap_Monad.execute (g x s z) h'' |
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| (Inr e, h'') \<Rightarrow> (Inr e, h'')) |
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| (Inr e, h') \<Rightarrow> (Inr e, h') |
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)" |
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by auto |
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lemma graph_implies_dom: |
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"mrec_graph x y \<Longrightarrow> mrec_dom x" |
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apply (induct rule:mrec_graph.induct) |
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apply (rule accpI) |
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apply (erule mrec_rel.cases) |
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by simp |
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lemma mrec_default: "\<not> mrec_dom (x, h) \<Longrightarrow> mrec x h = (Inr Exn, undefined)" |
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unfolding mrec_def |
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by (rule fundef_default_value[OF mrec_sumC_def graph_implies_dom, of _ _ "(x, h)", simplified]) |
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lemma mrec_di_reverse: |
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assumes "\<not> mrec_dom (x, h)" |
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shows " |
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(case Heap_Monad.execute (f x) h of |
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(Inl (Inl r), h') \<Rightarrow> False |
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| (Inl (Inr s), h') \<Rightarrow> \<not> mrec_dom (s, h') |
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| (Inr e, h') \<Rightarrow> False |
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)" |
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using assms |
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by (auto split:prod.splits sum.splits) |
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(erule notE, rule accpI, elim mrec_rel.cases, simp)+ |
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parents:
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|
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lemma mrec_rule: |
36057 | 311 |
"mrec x h = |
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|
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(case Heap_Monad.execute (f x) h of |
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(Inl (Inl r), h') \<Rightarrow> (Inl r, h') |
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| (Inl (Inr s), h') \<Rightarrow> |
36057 | 315 |
(case mrec s h' of |
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|
316 |
(Inl z, h'') \<Rightarrow> Heap_Monad.execute (g x s z) h'' |
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|
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| (Inr e, h'') \<Rightarrow> (Inr e, h'')) |
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|
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| (Inr e, h') \<Rightarrow> (Inr e, h') |
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|
319 |
)" |
36057 | 320 |
apply (cases "mrec_dom (x,h)", simp) |
321 |
apply (frule mrec_default) |
|
322 |
apply (frule mrec_di_reverse, simp) |
|
323 |
by (auto split: sum.split prod.split simp: mrec_default) |
|
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|
324 |
|
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|
325 |
|
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|
326 |
definition |
36057 | 327 |
"MREC x = Heap (mrec x)" |
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|
328 |
|
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|
329 |
lemma MREC_rule: |
36057 | 330 |
"MREC x = |
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|
331 |
(do y \<leftarrow> f x; |
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|
332 |
(case y of |
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|
333 |
Inl r \<Rightarrow> return r |
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|
334 |
| Inr s \<Rightarrow> |
36057 | 335 |
do z \<leftarrow> MREC s ; |
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|
336 |
g x s z |
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|
337 |
done) done)" |
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|
338 |
unfolding MREC_def |
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|
339 |
unfolding bindM_def return_def |
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|
340 |
apply simp |
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added Imperative_HOL examples; added tail-recursive combinator for monadic heap functions; adopted code generation of references; added lemmas
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|
341 |
apply (rule ext) |
36057 | 342 |
apply (unfold mrec_rule[of x]) |
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|
343 |
by (auto split:prod.splits sum.splits) |
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|
344 |
|
36057 | 345 |
|
346 |
lemma MREC_pinduct: |
|
347 |
assumes "Heap_Monad.execute (MREC x) h = (Inl r, h')" |
|
348 |
assumes non_rec_case: "\<And> x h h' r. Heap_Monad.execute (f x) h = (Inl (Inl r), h') \<Longrightarrow> P x h h' r" |
|
349 |
assumes rec_case: "\<And> x h h1 h2 h' s z r. Heap_Monad.execute (f x) h = (Inl (Inr s), h1) \<Longrightarrow> Heap_Monad.execute (MREC s) h1 = (Inl z, h2) \<Longrightarrow> P s h1 h2 z |
|
350 |
\<Longrightarrow> Heap_Monad.execute (g x s z) h2 = (Inl r, h') \<Longrightarrow> P x h h' r" |
|
351 |
shows "P x h h' r" |
|
352 |
proof - |
|
353 |
from assms(1) have mrec: "mrec x h = (Inl r, h')" |
|
354 |
unfolding MREC_def execute.simps . |
|
355 |
from mrec have dom: "mrec_dom (x, h)" |
|
356 |
apply - |
|
357 |
apply (rule ccontr) |
|
358 |
apply (drule mrec_default) by auto |
|
359 |
from mrec have h'_r: "h' = (snd (mrec x h))" "r = (Sum_Type.Projl (fst (mrec x h)))" |
|
360 |
by auto |
|
361 |
from mrec have "P x h (snd (mrec x h)) (Sum_Type.Projl (fst (mrec x h)))" |
|
362 |
proof (induct arbitrary: r h' rule: mrec.pinduct[OF dom]) |
|
363 |
case (1 x h) |
|
364 |
obtain rr h' where "mrec x h = (rr, h')" by fastsimp |
|
365 |
obtain fret h1 where exec_f: "Heap_Monad.execute (f x) h = (fret, h1)" by fastsimp |
|
366 |
show ?case |
|
367 |
proof (cases fret) |
|
368 |
case (Inl a) |
|
369 |
note Inl' = this |
|
370 |
show ?thesis |
|
371 |
proof (cases a) |
|
372 |
case (Inl aa) |
|
373 |
from this Inl' 1(1) exec_f mrec non_rec_case show ?thesis |
|
374 |
by auto |
|
375 |
next |
|
376 |
case (Inr b) |
|
377 |
note Inr' = this |
|
378 |
obtain ret_mrec h2 where mrec_rec: "mrec b h1 = (ret_mrec, h2)" by fastsimp |
|
379 |
from this Inl 1(1) exec_f mrec show ?thesis |
|
380 |
proof (cases "ret_mrec") |
|
381 |
case (Inl aaa) |
|
382 |
from this mrec exec_f Inl' Inr' 1(1) mrec_rec 1(2)[OF exec_f Inl' Inr', of "aaa" "h2"] 1(3) |
|
383 |
show ?thesis |
|
384 |
apply auto |
|
385 |
apply (rule rec_case) |
|
386 |
unfolding MREC_def by auto |
|
387 |
next |
|
388 |
case (Inr b) |
|
389 |
from this Inl 1(1) exec_f mrec Inr' mrec_rec 1(3) show ?thesis by auto |
|
390 |
qed |
|
391 |
qed |
|
392 |
next |
|
393 |
case (Inr b) |
|
394 |
from this 1(1) mrec exec_f 1(3) show ?thesis by simp |
|
395 |
qed |
|
396 |
qed |
|
397 |
from this h'_r show ?thesis by simp |
|
398 |
qed |
|
399 |
||
400 |
end |
|
401 |
||
402 |
text {* Providing global versions of the constant and the theorems *} |
|
403 |
||
404 |
abbreviation "MREC == mrec.MREC" |
|
405 |
lemmas MREC_rule = mrec.MREC_rule |
|
406 |
lemmas MREC_pinduct = mrec.MREC_pinduct |
|
407 |
||
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replaced generic 'hide' command by more conventional 'hide_class', 'hide_type', 'hide_const', 'hide_fact' -- frees some popular keywords;
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parents:
36078
diff
changeset
|
408 |
hide_const (open) heap execute |
26170 | 409 |
|
26182 | 410 |
|
411 |
subsection {* Code generator setup *} |
|
412 |
||
413 |
subsubsection {* Logical intermediate layer *} |
|
414 |
||
415 |
definition |
|
31205
98370b26c2ce
String.literal replaces message_string, code_numeral replaces (code_)index
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31058
diff
changeset
|
416 |
Fail :: "String.literal \<Rightarrow> exception" |
26182 | 417 |
where |
28562 | 418 |
[code del]: "Fail s = Exn" |
26182 | 419 |
|
420 |
definition |
|
421 |
raise_exc :: "exception \<Rightarrow> 'a Heap" |
|
422 |
where |
|
28562 | 423 |
[code del]: "raise_exc e = raise []" |
26182 | 424 |
|
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prefer code_inline over code_unfold; use code_unfold_post where appropriate
haftmann
parents:
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diff
changeset
|
425 |
lemma raise_raise_exc [code, code_unfold]: |
26182 | 426 |
"raise s = raise_exc (Fail (STR s))" |
427 |
unfolding Fail_def raise_exc_def raise_def .. |
|
428 |
||
36176
3fe7e97ccca8
replaced generic 'hide' command by more conventional 'hide_class', 'hide_type', 'hide_const', 'hide_fact' -- frees some popular keywords;
wenzelm
parents:
36078
diff
changeset
|
429 |
hide_const (open) Fail raise_exc |
26182 | 430 |
|
431 |
||
27707 | 432 |
subsubsection {* SML and OCaml *} |
26182 | 433 |
|
26752 | 434 |
code_type Heap (SML "unit/ ->/ _") |
26182 | 435 |
code_const Heap (SML "raise/ (Fail/ \"bare Heap\")") |
27826 | 436 |
code_const "op \<guillemotright>=" (SML "!(fn/ f'_/ =>/ fn/ ()/ =>/ f'_/ (_/ ())/ ())") |
27707 | 437 |
code_const return (SML "!(fn/ ()/ =>/ _)") |
26182 | 438 |
code_const "Heap_Monad.Fail" (SML "Fail") |
27707 | 439 |
code_const "Heap_Monad.raise_exc" (SML "!(fn/ ()/ =>/ raise/ _)") |
26182 | 440 |
|
441 |
code_type Heap (OCaml "_") |
|
442 |
code_const Heap (OCaml "failwith/ \"bare Heap\"") |
|
27826 | 443 |
code_const "op \<guillemotright>=" (OCaml "!(fun/ f'_/ ()/ ->/ f'_/ (_/ ())/ ())") |
27707 | 444 |
code_const return (OCaml "!(fun/ ()/ ->/ _)") |
26182 | 445 |
code_const "Heap_Monad.Fail" (OCaml "Failure") |
27707 | 446 |
code_const "Heap_Monad.raise_exc" (OCaml "!(fun/ ()/ ->/ raise/ _)") |
447 |
||
31871 | 448 |
setup {* |
449 |
||
450 |
let |
|
27707 | 451 |
|
31871 | 452 |
open Code_Thingol; |
453 |
||
454 |
fun imp_program naming = |
|
27707 | 455 |
|
31871 | 456 |
let |
457 |
fun is_const c = case lookup_const naming c |
|
458 |
of SOME c' => (fn c'' => c' = c'') |
|
459 |
| NONE => K false; |
|
460 |
val is_bindM = is_const @{const_name bindM}; |
|
461 |
val is_return = is_const @{const_name return}; |
|
31893 | 462 |
val dummy_name = ""; |
31871 | 463 |
val dummy_type = ITyVar dummy_name; |
31893 | 464 |
val dummy_case_term = IVar NONE; |
31871 | 465 |
(*assumption: dummy values are not relevant for serialization*) |
466 |
val unitt = case lookup_const naming @{const_name Unity} |
|
467 |
of SOME unit' => IConst (unit', (([], []), [])) |
|
468 |
| NONE => error ("Must include " ^ @{const_name Unity} ^ " in generated constants."); |
|
469 |
fun dest_abs ((v, ty) `|=> t, _) = ((v, ty), t) |
|
470 |
| dest_abs (t, ty) = |
|
471 |
let |
|
472 |
val vs = fold_varnames cons t []; |
|
473 |
val v = Name.variant vs "x"; |
|
474 |
val ty' = (hd o fst o unfold_fun) ty; |
|
31893 | 475 |
in ((SOME v, ty'), t `$ IVar (SOME v)) end; |
31871 | 476 |
fun force (t as IConst (c, _) `$ t') = if is_return c |
477 |
then t' else t `$ unitt |
|
478 |
| force t = t `$ unitt; |
|
479 |
fun tr_bind' [(t1, _), (t2, ty2)] = |
|
480 |
let |
|
481 |
val ((v, ty), t) = dest_abs (t2, ty2); |
|
482 |
in ICase (((force t1, ty), [(IVar v, tr_bind'' t)]), dummy_case_term) end |
|
483 |
and tr_bind'' t = case unfold_app t |
|
484 |
of (IConst (c, (_, ty1 :: ty2 :: _)), [x1, x2]) => if is_bindM c |
|
485 |
then tr_bind' [(x1, ty1), (x2, ty2)] |
|
486 |
else force t |
|
487 |
| _ => force t; |
|
31893 | 488 |
fun imp_monad_bind'' ts = (SOME dummy_name, dummy_type) `|=> ICase (((IVar (SOME dummy_name), dummy_type), |
31871 | 489 |
[(unitt, tr_bind' ts)]), dummy_case_term) |
490 |
and imp_monad_bind' (const as (c, (_, tys))) ts = if is_bindM c then case (ts, tys) |
|
491 |
of ([t1, t2], ty1 :: ty2 :: _) => imp_monad_bind'' [(t1, ty1), (t2, ty2)] |
|
492 |
| ([t1, t2, t3], ty1 :: ty2 :: _) => imp_monad_bind'' [(t1, ty1), (t2, ty2)] `$ t3 |
|
493 |
| (ts, _) => imp_monad_bind (eta_expand 2 (const, ts)) |
|
494 |
else IConst const `$$ map imp_monad_bind ts |
|
495 |
and imp_monad_bind (IConst const) = imp_monad_bind' const [] |
|
496 |
| imp_monad_bind (t as IVar _) = t |
|
497 |
| imp_monad_bind (t as _ `$ _) = (case unfold_app t |
|
498 |
of (IConst const, ts) => imp_monad_bind' const ts |
|
499 |
| (t, ts) => imp_monad_bind t `$$ map imp_monad_bind ts) |
|
500 |
| imp_monad_bind (v_ty `|=> t) = v_ty `|=> imp_monad_bind t |
|
501 |
| imp_monad_bind (ICase (((t, ty), pats), t0)) = ICase |
|
502 |
(((imp_monad_bind t, ty), |
|
503 |
(map o pairself) imp_monad_bind pats), |
|
504 |
imp_monad_bind t0); |
|
28663
bd8438543bf2
code identifier namings are no longer imperative
haftmann
parents:
28562
diff
changeset
|
505 |
|
31871 | 506 |
in (Graph.map_nodes o map_terms_stmt) imp_monad_bind end; |
27707 | 507 |
|
508 |
in |
|
509 |
||
31871 | 510 |
Code_Target.extend_target ("SML_imp", ("SML", imp_program)) |
511 |
#> Code_Target.extend_target ("OCaml_imp", ("OCaml", imp_program)) |
|
27707 | 512 |
|
513 |
end |
|
31871 | 514 |
|
27707 | 515 |
*} |
516 |
||
26182 | 517 |
code_reserved OCaml Failure raise |
518 |
||
519 |
||
520 |
subsubsection {* Haskell *} |
|
521 |
||
522 |
text {* Adaption layer *} |
|
523 |
||
29793 | 524 |
code_include Haskell "Heap" |
26182 | 525 |
{*import qualified Control.Monad; |
526 |
import qualified Control.Monad.ST; |
|
527 |
import qualified Data.STRef; |
|
528 |
import qualified Data.Array.ST; |
|
529 |
||
27695 | 530 |
type RealWorld = Control.Monad.ST.RealWorld; |
26182 | 531 |
type ST s a = Control.Monad.ST.ST s a; |
532 |
type STRef s a = Data.STRef.STRef s a; |
|
27673 | 533 |
type STArray s a = Data.Array.ST.STArray s Int a; |
26182 | 534 |
|
535 |
newSTRef = Data.STRef.newSTRef; |
|
536 |
readSTRef = Data.STRef.readSTRef; |
|
537 |
writeSTRef = Data.STRef.writeSTRef; |
|
538 |
||
27673 | 539 |
newArray :: (Int, Int) -> a -> ST s (STArray s a); |
26182 | 540 |
newArray = Data.Array.ST.newArray; |
541 |
||
27673 | 542 |
newListArray :: (Int, Int) -> [a] -> ST s (STArray s a); |
26182 | 543 |
newListArray = Data.Array.ST.newListArray; |
544 |
||
27673 | 545 |
lengthArray :: STArray s a -> ST s Int; |
546 |
lengthArray a = Control.Monad.liftM snd (Data.Array.ST.getBounds a); |
|
26182 | 547 |
|
27673 | 548 |
readArray :: STArray s a -> Int -> ST s a; |
26182 | 549 |
readArray = Data.Array.ST.readArray; |
550 |
||
27673 | 551 |
writeArray :: STArray s a -> Int -> a -> ST s (); |
26182 | 552 |
writeArray = Data.Array.ST.writeArray;*} |
553 |
||
29793 | 554 |
code_reserved Haskell Heap |
26182 | 555 |
|
556 |
text {* Monad *} |
|
557 |
||
29793 | 558 |
code_type Heap (Haskell "Heap.ST/ Heap.RealWorld/ _") |
27695 | 559 |
code_const Heap (Haskell "error/ \"bare Heap\"") |
28145 | 560 |
code_monad "op \<guillemotright>=" Haskell |
26182 | 561 |
code_const return (Haskell "return") |
562 |
code_const "Heap_Monad.Fail" (Haskell "_") |
|
563 |
code_const "Heap_Monad.raise_exc" (Haskell "error") |
|
564 |
||
26170 | 565 |
end |