static methods (+ bug in example)

doc/contextual_checks.md

@@ -11,7 +11,7 @@
 * No duplicate static attribute declaration
 * No duplicate instance attribute declaration
 * No duplicate instance method declaration
-* (**Missing**) No duplicate static method declaration
+* No duplicate static method declaration
 * Herited class exists
 * No cycle in inheritance graph
 

lib/ast.ml

@@ -49,7 +49,6 @@ type ctorDecl = {
 
 type methodDecl = {
   name: string;
-  static: bool;
   override: bool;
   params: param list;
   retType: string option;
@@ -59,7 +58,8 @@ type methodDecl = {
 
 type classBody = {
   ctor: ctorDecl;
-  methods: methodDecl list;
+  staticMethods: methodDecl list;
+  instMethods: methodDecl list;
   staticAttrs: param list;
   instAttrs: param list;
 }

lib/astmanip.ml

@@ -29,7 +29,7 @@ let rec ancestors decls decl =
     with a given name. *)
 
 let rec find_method_opt decls name decl =
-  List.find_opt (fun (meth: methodDecl) -> meth.name = name) decl.body.methods
+  List.find_opt (fun (meth: methodDecl) -> meth.name = name) decl.body.instMethods
   |> Optmanip.or_else (fun () ->
       match decl.superclass with
       | None -> None
@@ -40,35 +40,58 @@ let rec find_method_opt decls name decl =
 
 (** Get the type of an attribute in a class declaration. *)
 
-let rec get_attr_opt attrName decl =
+let rec get_inst_attr_opt attrName decl =
   let pred (attr: param) =
     if attr.name = attrName then Some(attr.className) else None
   in let pred2 (attr: ctorParam) =
        if attr.name = attrName then Some(attr.className) else None
-  in
-  List.find_map pred decl.body.instAttrs
-  |> Optmanip.or_else (fun () ->
-      List.find_map pred decl.body.staticAttrs
-    )
-  |> Optmanip.or_else (fun () ->
-      List.find_map pred2 decl.ctorParams
-    )
+  in List.find_map pred decl.body.instAttrs
+     |> Optmanip.or_else (fun () ->
+         List.find_map pred2 decl.ctorParams
+       )
 
 (** Get the type of an attribute in a class declaration.
     @raise Not_found if the class has no such attribute. *)
 
-let get_attr attrName decl =
-  get_attr_opt attrName decl
+let get_inst_attr attrName decl =
+  get_inst_attr_opt attrName decl
   |> Optmanip.get_or_else (fun () ->
-      Printf.eprintf "[ERR] get_attr '%s' failed\n" attrName;
+      Printf.eprintf "[ERR] get_inst_attr '%s' failed\n" attrName;
+      raise Not_found
+    )
+
+(** Get the type of a static attribute in a class declaration. *)
+
+let rec get_static_attr_opt attrName decl =
+  let pred (attr: param) =
+    if attr.name = attrName then Some(attr.className) else None
+  in List.find_map pred decl.body.staticAttrs
+
+(** Get the type of a static attribute in a class declaration.
+    @raise Not_found if the class has no such attribute. *)
+
+let get_static_attr attrName decl =
+  get_static_attr_opt attrName decl
+  |> Optmanip.get_or_else (fun () ->
+      Printf.eprintf "[ERR] get_static_attr '%s' failed\n" attrName;
       raise Not_found
     )
 
 (** Get the type of a method in a class declaration.
     Note: procedures have the special type 'Void' *)
 
-let get_method_type methName decl =
-  decl.body.methods
+let get_inst_method_type methName decl =
+  decl.body.instMethods
+  |> List.find_map  (fun (meth: methodDecl) ->
+      if meth.name = methName then meth.retType else None
+    )
+  |> Optmanip.get_or("Void")
+
+(** Get the type of a static method in a class declaration.
+    Note: procedures have the special type 'Void' *)
+
+let get_static_method_type methName decl =
+  decl.body.staticMethods
   |> List.find_map  (fun (meth: methodDecl) ->
       if meth.name = methName then meth.retType else None
     )
@@ -86,23 +109,23 @@ let get_expr_type decls env expr =
 
     | Attr(e, attrName) ->
       let decl = find_class decls (r_get e)
-      in get_attr attrName decl
+      in get_inst_attr attrName decl
 
     | StaticAttr(className, attrName) ->
       let decl = find_class decls className
-      in get_attr attrName decl
+      in get_static_attr attrName decl
 
     | List l ->
       let last = List.hd (List.rev l)
       in r_get last
 
     | Call(caller, name, _args) ->
       let decl = find_class decls (r_get caller)
-      in get_method_type name decl
+      in get_inst_method_type name decl
 
     | StaticCall(className, name, _args) ->
       let decl = find_class decls className
-      in get_method_type name decl
+      in get_static_method_type name decl
 
     | New(className, _args) -> className
 

lib/contextual.ml

@@ -8,7 +8,8 @@ exception Contextual_error of string
     @raise Contextual_error if a check fails. *)
 
 let check_no_dup decl =
-  let methods = decl.body.methods |> List.map (fun (m: methodDecl) -> m.name)
+  let instMethods = decl.body.instMethods |> List.map (fun (m: methodDecl) -> m.name)
+  in let staticMethods = decl.body.staticMethods |> List.map (fun (m: methodDecl) -> m.name)
   in let staticAttrs = decl.body.staticAttrs |> List.map (fun (a: param) -> a.name)
   in let instAttrs = decl.body.instAttrs |> List.map (fun (a: param) -> a.name)
 
@@ -19,9 +20,10 @@ let check_no_dup decl =
         then raise @@ Contextual_error (Printf.sprintf "multiple definition %s of '%s' in class '%s'" t e decl.name)
         else check t r
 
-  in check "method" methods;
-  check "static attribute" staticAttrs;
-  check "instance attribute" instAttrs
+  in check "method" instMethods;
+  check "static method" staticMethods;
+  check "attribute" instAttrs;
+  check "static attribute" staticAttrs
 
 (** Check that each class declaration extends a declared class, if any.
     @raise Contextual_error if a check fails. *)
@@ -90,8 +92,8 @@ let check_overrides decls decl =
   in match decl.superclass with
   | Some(super) ->
     let superDecl = find_class decls super
-    in List.iter (check_super_method superDecl) decl.body.methods
-  | None -> List.iter check_base_method decl.body.methods
+    in List.iter (check_super_method superDecl) decl.body.instMethods
+  | None -> List.iter check_base_method decl.body.instMethods
 
 (** Checks that id is in scope.
     @raise Contextual_error if a check fails. *)
@@ -110,10 +112,9 @@ let rec check_method_calls _env _expr _instr =
 
 (** Performs the following checks:
     - All code paths lead to either:
-      (a) A return, or
+      (a) A return instruction, or
       (b) an assign to the implicit 'result' variable.
-    - All return instructions have a type compatible with the return type
-    - All assigns to result have a type compatible with the return type *)
+    - All return instructions have a type compatible with the return type *)
 
 let check_returns decls env retType instr =
 
@@ -292,7 +293,7 @@ and check_expr_attr decls env (e, name) =
   check_expr decls env e;
   let t = get_expr_type decls env e
   in let decl = find_class decls t
-  in let attr = get_attr_opt name decl
+  in let attr = get_inst_attr_opt name decl
   in if Option.is_none attr
   then raise @@ Contextual_error (Printf.sprintf "no attribute named '%s' in class '%s'" name t)
 
@@ -301,7 +302,7 @@ and check_expr_attr decls env (e, name) =
 
 and check_expr_static_attr decls (t, name) =
   let decl = find_class decls t
-  in let attr = get_attr_opt name decl
+  in let attr = get_static_attr_opt name decl
   in if Option.is_none attr
   then raise @@ Contextual_error (Printf.sprintf "no static attribute named '%s' in class '%s'" name t)
 
@@ -320,7 +321,15 @@ and check_expr decls env expr =
 
 (* -------------------------------------------------------------------------- *)
 
-let check_method decls env meth =
+let check_static_method decls env meth =
+  check_no_reserved_var meth.params;
+  let env = make_method_env env meth
+  in check_instr decls env meth.body;
+  match meth.retType with
+  | Some(ret) -> check_returns decls env ret meth.body
+  | None -> check_no_return meth.body
+
+let check_instance_method decls env meth =
   check_no_reserved_var meth.params;
   let env = make_method_env env meth
   in check_instr decls env meth.body;
@@ -338,7 +347,8 @@ let check_decl decls decl =
     check_overrides decls decl;
     check_no_dup decl;
     let env = make_class_env decl
-    in List.iter (check_method decls env) decl.body.methods
+    in List.iter (check_instance_method decls env) decl.body.instMethods;
+    List.iter (check_static_method decls []) decl.body.staticMethods
   end
 
 let check_decls decls =

lib/parser.mly

@@ -2,25 +2,27 @@
 open Ast
 
 type classBodyElt =
-  | Method of Ast.methodDecl
+  | StaticMethod of Ast.methodDecl
+  | InstMethod of Ast.methodDecl
   | Ctor of Ast.ctorDecl
   | StaticAttrib of Ast.param list
   | InstAttrib of Ast.param list
 
 let split_body_elts l =
 
-  let rec r_partition l (lm, lc, ls, li) =
+  let rec r_partition l (lsm, lim, lc, lsa, lia) =
     match l with
-    | [] -> (lm, lc, ls, li)
+    | [] -> (lsm, lim, lc, lsa, lia)
     | e::r ->
       let res =  (match e with
-        | Method m -> (m::lm, lc, ls, li)
-        | Ctor c -> (lm, c::lc, ls, li)
-        | StaticAttrib s -> (lm, lc, s@ls, li)
-        | InstAttrib i -> (lm, lc, ls, i@li))
+        | StaticMethod m -> (m::lsm, lim, lc, lsa, lia)
+        | InstMethod m -> (lsm, m::lim, lc, lsa, lia)
+        | Ctor c -> (lsm, lim, c::lc, lsa, lia)
+        | StaticAttrib s -> (lsm, lim, lc, s@lsa, lia)
+        | InstAttrib i -> (lsm, lim, lc, lsa, i@lia))
       in r_partition r res
 
-  in r_partition l ([], [], [], [])
+  in r_partition l ([], [], [], [], [])
 %}
 
 (* Class Keywords *)
@@ -71,9 +73,9 @@ classDecl:
 
 classBody:
   LCURLY l = list(classBodyElement) RCURLY {
-    let (lm, lc, ls, li) = split_body_elts l
+    let (lsm, lim, lc, lsa, lia) = split_body_elts l
     in let ctor = List.hd lc (* TODO: make sure there is only one ctor *)
-    in { methods=lm; ctor; staticAttrs=ls; instAttrs=li }
+    in { staticMethods=lsm; instMethods=lim; ctor; staticAttrs=lsa; instAttrs=lia }
   }
 
 classBodyElement:
@@ -83,10 +85,12 @@ classBodyElement:
 
 methodDecl:
   | DEF static = boption(STATIC) override = boption(OVERRIDE) name = ID params = paramList retType = option(preceded(COLON, CLASSNAME)) IS body = instrBlock {
-     Method({ name; static; override; params; retType; body;  })
+    let ctor args = if static then StaticMethod args else InstMethod args
+    in ctor({ name; override; params; retType; body;  })
   }
   | DEF static = boption(STATIC) override = boption(OVERRIDE) name = ID params = paramList COLON retType = CLASSNAME ASSIGN e = expr {
-    Method({ name; static; override; params; retType=Some(retType); body=Return(e); })
+    let ctor args = if static then StaticMethod args else InstMethod args
+    in ctor({ name; override; params; retType=Some(retType); body=Return(e); })
   }
 
 ctorDecl:

progs/ex1.kat

@@ -117,9 +117,9 @@ class CouleurFactory() is {
       CouleurFactory.theNoir  := new Couleur(1);
       CouleurFactory.theGris  := new Couleur(2);
    }
-   def blanc() : Couleur := CouleurFactory.theBlanc
-   def noir()  : Couleur := CouleurFactory.theNoir
-   def gris()  : Couleur := CouleurFactory.theGris
+   def static blanc() : Couleur := CouleurFactory.theBlanc
+   def static noir()  : Couleur := CouleurFactory.theNoir
+   def static gris()  : Couleur := CouleurFactory.theGris
 }
 
 /* ci-dessous on ne met pas var devant x et y sinon ca definirait deux