From d783dd58557246a85a7b1227e04b14264086019b Mon Sep 17 00:00:00 2001
From: OopsOverflow <houssemmahmoudswe@gmail.com>
Date: Mon, 10 Jan 2022 16:41:55 +0100
Subject: [PATCH] add static cast expr

---
 lib/ast.ml        |  1 +
 lib/astmanip.ml   |  1 +
 lib/contextual.ml | 27 +++++++++++++++++++--------
 lib/misc.ml       |  1 +
 lib/parser.mly    |  1 +
 progs/err1.kat    | 14 --------------
 progs/errCast.kat |  2 +-
 7 files changed, 24 insertions(+), 23 deletions(-)

diff --git a/lib/ast.ml b/lib/ast.ml
index 4feb618..a0b923c 100644
--- a/lib/ast.ml
+++ b/lib/ast.ml
@@ -37,6 +37,7 @@ and expr =
   | String of string
   | StrCat of expr * expr
   | New of string * expr list
+  | StaticCast of string * expr
 [@@deriving show]
 
 type ctorDecl = {
diff --git a/lib/astmanip.ml b/lib/astmanip.ml
index fa5a1b7..8ddf899 100644
--- a/lib/astmanip.ml
+++ b/lib/astmanip.ml
@@ -148,6 +148,7 @@ let get_expr_type decls env expr =
       in get_static_method_type name decl
 
     | New(className, _args) -> className
+    | StaticCast(className, _args) -> className 
 
   in r_get expr
 
diff --git a/lib/contextual.ml b/lib/contextual.ml
index 9ec264c..088c3dc 100644
--- a/lib/contextual.ml
+++ b/lib/contextual.ml
@@ -183,7 +183,7 @@ let check_no_reserved_class decls =
 
   in let check decl =
        if List.exists (fun r -> decl.name = r || decl.superclass = Some(r)) reserved
-       then err (Printf.sprintf "use of reserved class name '%s'" decl.name)
+       then err (Printf.sprintf "use of reserved class in class '%s'" decl.name)
 
   in List.iter check decls
 
@@ -198,13 +198,13 @@ let rec check_no_dup_class = function
     else check_no_dup_class decls
 
 (** Check constructor declaration validity. Performs following checks:
-    - Constructor name and class name are equal
-    - Constructor parameters and class parameters are equal
-    - Constructor parameters have no reserved keywords
-    - Constructor calls the right super constructor if class is derived
-    - Constructor does not call any super constructor if class is base
-    - No return instruction in body
-      @raise Contextual_error if a check fails.
+    * Constructor name and class name are equal
+    * Constructor parameters and class parameters are equal
+    * Constructor parameters have no reserved keywords
+    * Constructor calls the right super constructor if class is derived
+    * Constructor does not call any super constructor if class is base
+    * No return instruction in body
+    @raise Contextual_error if a check fails.
 *)
 
 let check_ctor decl =
@@ -393,6 +393,16 @@ and check_expr_new decls env (className, args) =
     List.iter2 (fun arg (param: ctorParam) ->
         check_arg arg param.className
       ) args decl.ctorParams
+and check_expr_cast decls env (className, e) = 
+  check_expr decls env e;
+  
+  let decl = find_class_opt decls className 
+  in match decl with 
+  | None -> err (Printf.sprintf "cast to unkown class '%s' " className)
+  | Some(_decl) -> 
+    let t = get_expr_type decls env e
+    in if not (is_base decls t className) 
+       then err(Printf.sprintf "cannot cast '%s' to '%s' " t className)   
 
 and check_expr_op decls env (e1, e2) =
   check_expr decls env e1;
@@ -425,6 +435,7 @@ and check_expr decls env expr =
   | BinOp(e1, _, e2) -> check_expr_op decls env (e1, e2)
   | StrCat(e1, e2) -> check_expr_strcat decls env (e1, e2)
   | New(className, args) -> check_expr_new decls env (className, args)
+  | StaticCast (className, e) -> check_expr_cast decls env (className, e)
   | Cste _ | String _ -> ()
 
 (* -------------------------------------------------------------------------- *)
diff --git a/lib/misc.ml b/lib/misc.ml
index fcccdbd..cd7270a 100644
--- a/lib/misc.ml
+++ b/lib/misc.ml
@@ -14,3 +14,4 @@ let string_of_expr_type e =
   | String _ -> "string literal"
   | StrCat _ -> "string concatenation"
   | New _ -> "instantiation"
+  | StaticCast _ -> "static cast"
diff --git a/lib/parser.mly b/lib/parser.mly
index e50a858..a88603c 100644
--- a/lib/parser.mly
+++ b/lib/parser.mly
@@ -165,3 +165,4 @@ expr:
   | MINUS rhs = expr { UMinus (rhs) }
   | PLUS rhs = expr { rhs }
   | NEW name = CLASSNAME LPAREN le = separated_list(COMMA, expr) RPAREN { New(name, le) }
+  | LPAREN c = CLASSNAME e = expr RPAREN { StaticCast(c, e) }
diff --git a/progs/err1.kat b/progs/err1.kat
index 4a22286..763e8e8 100644
--- a/progs/err1.kat
+++ b/progs/err1.kat
@@ -9,20 +9,6 @@ class Point(xc: Integer, yc: Integer) is {
   }
 
 
-  def setName(s: String) : Point is {
-      this.name := s;
-      result := this;
-      return;
-      this.super := s; /* interdit */
-  }
-
-  def print() is { 
-      this.name.println();
-      this := new Point(0, 0);   /* interdit */
-      this.x := this.super.x; /* incorrect */
-      result := this;	 /* interdit car pas de type de retour. */
-  }
-
 }
 { 
   p, p2: Point
diff --git a/progs/errCast.kat b/progs/errCast.kat
index cfc35a9..36e35be 100644
--- a/progs/errCast.kat
+++ b/progs/errCast.kat
@@ -38,7 +38,7 @@ is {
   monB  := new B();
   
   /* (A monA3).h().toString.println(); /* KO: h indefinie dans A */
-  /* (A4 monA3); /* KO: pas de cast descendant */
+   (A4 monA3); /* KO: pas de cast descendant */
   (A3 monA4); /* OK */
   /* (A3 monA); /* KO: pas de cast descendant */
   /* (A2 monA4).k(); /* KO: pas de k() dans A2 */