ProgTutorial/Advanced.thy
changeset 395 2c392f61f400
parent 394 0019ebf76e10
child 396 a2e49e0771b3
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ProgTutorial/Advanced.thy	Thu Nov 19 17:48:44 2009 +0100
@@ -0,0 +1,236 @@
+theory Advanced
+imports Base FirstSteps
+begin
+
+(*<*)
+setup{*
+open_file_with_prelude 
+  "Advanced_Code.thy"
+  ["theory General", "imports Base FirstSteps", "begin"]
+*}
+(*>*)
+
+
+chapter {* Advanced Isabelle *}
+
+text {*
+  TBD
+*}
+
+section {* Theories\label{sec:theories} (TBD) *}
+
+text {*
+  Theories are the most fundamental building blocks in Isabelle. They 
+  contain definitions, syntax declarations, axioms, proofs etc. If a definition
+  is stated, it must be stored in a theory in order to be usable later
+  on. Similar with proofs: once a proof is finished, the proved theorem
+  needs to be stored in the theorem database of the theory in order to
+  be usable. All relevant data of a theort can be querried as follows.
+
+  \begin{isabelle}
+  \isacommand{print\_theory}\\
+  @{text "> names: Pure Code_Generator HOL \<dots>"}\\
+  @{text "> classes: Inf < type \<dots>"}\\
+  @{text "> default sort: type"}\\
+  @{text "> syntactic types: #prop \<dots>"}\\
+  @{text "> logical types: 'a \<times> 'b \<dots>"}\\
+  @{text "> type arities: * :: (random, random) random \<dots>"}\\
+  @{text "> logical constants: == :: 'a \<Rightarrow> 'a \<Rightarrow> prop \<dots>"}\\
+  @{text "> abbreviations: \<dots>"}\\
+  @{text "> axioms: \<dots>"}\\
+  @{text "> oracles: \<dots>"}\\
+  @{text "> definitions: \<dots>"}\\
+  @{text "> theorems: \<dots>"}
+  \end{isabelle}
+
+  \begin{center}
+  \begin{tikzpicture}
+  \node[top color=white, bottom color=gray!30, draw=black!100, drop shadow] {A};
+  \end{tikzpicture}
+  \end{center}
+
+
+  In contrast to an ordinary theory, which simply consists of a type
+  signature, as well as tables for constants, axioms and theorems, a local
+  theory contains additional context information, such as locally fixed
+  variables and local assumptions that may be used by the package. The type
+  @{ML_type local_theory} is identical to the type of \emph{proof contexts}
+  @{ML_type "Proof.context"}, although not every proof context constitutes a
+  valid local theory.
+
+  @{ML "Context.>> o Context.map_theory"}
+
+  \footnote{\bf FIXME: list append in merge operations can cause 
+  exponential blowups.}
+*}
+
+section {* Setups (TBD) *}
+
+text {*
+  @{ML Sign.declare_const}
+
+  In the previous section we used \isacommand{setup} in order to make
+  a theorem attribute known to Isabelle. What happens behind the scenes
+  is that \isacommand{setup} expects a function of type 
+  @{ML_type "theory -> theory"}: the input theory is the current theory and the 
+  output the theory where the theory attribute has been stored.
+  
+  This is a fundamental principle in Isabelle. A similar situation occurs 
+  for example with declaring constants. The function that declares a 
+  constant on the ML-level is @{ML_ind  add_consts_i in Sign}. 
+  If you write\footnote{Recall that ML-code  needs to be 
+  enclosed in \isacommand{ML}~@{text "\<verbopen> \<dots> \<verbclose>"}.} 
+*}  
+
+ML{*Sign.add_consts_i [(@{binding "BAR"}, @{typ "nat"}, NoSyn)] @{theory} *}
+
+text {*
+  for declaring the constant @{text "BAR"} with type @{typ nat} and 
+  run the code, then you indeed obtain a theory as result. But if you 
+  query the constant on the Isabelle level using the command \isacommand{term}
+
+  \begin{isabelle}
+  \isacommand{term}~@{text [quotes] "BAR"}\\
+  @{text "> \"BAR\" :: \"'a\""}
+  \end{isabelle}
+
+  you do not obtain a constant of type @{typ nat}, but a free variable (printed in 
+  blue) of polymorphic type. The problem is that the ML-expression above did 
+  not register the declaration with the current theory. This is what the command
+  \isacommand{setup} is for. The constant is properly declared with
+*}
+
+setup %gray {* Sign.add_consts_i [(@{binding "BAR"}, @{typ "nat"}, NoSyn)] *}
+
+text {* 
+  Now 
+  
+  \begin{isabelle}
+  \isacommand{term}~@{text [quotes] "BAR"}\\
+  @{text "> \"BAR\" :: \"nat\""}
+  \end{isabelle}
+
+  returns a (black) constant with the type @{typ nat}.
+
+  A similar command is \isacommand{local\_setup}, which expects a function
+  of type @{ML_type "local_theory -> local_theory"}. Later on we will also
+  use the commands \isacommand{method\_setup} for installing methods in the
+  current theory and \isacommand{simproc\_setup} for adding new simprocs to
+  the current simpset.
+*}
+
+section {* Contexts (TBD) *}
+
+section {* Local Theories (TBD) *}
+
+text {*
+  @{ML_ind "Local_Theory.declaration"}
+*}
+
+(*
+setup {*
+ Sign.add_consts_i [(Binding"bar", @{typ "nat"},NoSyn)] 
+*}
+lemma "bar = (1::nat)"
+  oops
+
+setup {*   
+  Sign.add_consts_i [("foo", @{typ "nat"},NoSyn)] 
+ #> PureThy.add_defs false [((@{binding "foo_def"}, 
+       Logic.mk_equals (Const ("FirstSteps.foo", @{typ "nat"}), @{term "1::nat"})), [])] 
+ #> snd
+*}
+*)
+(*
+lemma "foo = (1::nat)"
+  apply(simp add: foo_def)
+  done
+
+thm foo_def
+*)
+
+section {* Morphisms (TBD) *}
+
+text {*
+  Morphisms are arbitrary transformations over terms, types, theorems and bindings.
+  They can be constructed using the function @{ML_ind morphism in Morphism},
+  which expects a record with functions of type
+
+  \begin{isabelle}
+  \begin{tabular}{rl}
+  @{text "binding:"} & @{text "binding -> binding"}\\
+  @{text "typ:"}     & @{text "typ -> typ"}\\
+  @{text "term:"}    & @{text "term -> term"}\\
+  @{text "fact:"}    & @{text "thm list -> thm list"}
+  \end{tabular}
+  \end{isabelle}
+
+  The simplest morphism is the  @{ML_ind identity in Morphism}-morphism defined as
+*}
+
+ML{*val identity = Morphism.morphism {binding = I, typ = I, term = I, fact = I}*}
+  
+text {*
+  Morphisms can be composed with the function @{ML_ind "$>" in Morphism}
+*}
+
+ML{*fun trm_phi (Free (x, T)) = Var ((x, 0), T) 
+  | trm_phi (Abs (x, T, t)) = Abs (x, T, trm_phi t)
+  | trm_phi (t $ s) = (trm_phi t) $ (trm_phi s)
+  | trm_phi t = t*}
+
+ML{*val phi = Morphism.term_morphism trm_phi*}
+
+ML{*Morphism.term phi @{term "P x y"}*}
+
+text {*
+  @{ML_ind term_morphism in Morphism}
+
+  @{ML_ind term in Morphism},
+  @{ML_ind thm in Morphism}
+
+  \begin{readmore}
+  Morphisms are implemented in the file @{ML_file "Pure/morphism.ML"}.
+  \end{readmore}
+*}
+
+section {* Misc (TBD) *}
+
+ML {*Datatype.get_info @{theory} "List.list"*}
+
+text {* 
+FIXME: association lists:
+@{ML_file "Pure/General/alist.ML"}
+
+FIXME: calling the ML-compiler
+
+*}
+
+section {* Managing Name Spaces (TBD) *}
+
+ML {* Sign.intern_type @{theory} "list" *}
+ML {* Sign.intern_const @{theory} "prod_fun" *}
+
+
+text {* 
+  @{ML_ind "Binding.str_of"} returns the string with markup;
+  @{ML_ind "Binding.name_of"} returns the string without markup
+
+  @{ML_ind "Binding.conceal"} 
+*}
+
+section {* Concurrency (TBD) *}
+
+text {*
+  @{ML_ind prove_future in Goal}
+  @{ML_ind future_result in Goal}
+  @{ML_ind fork_pri in Future}
+*}
+
+section {* Summary *}
+
+text {*
+  TBD
+*}
+
+end