Update typing.ml

Add find_var that search var in environment

src/typing.ml

@@ -3,11 +3,36 @@
 open Lang
 
 (* Environments *)
+type environment = {
+    localvars: (vname * tp) list; 
+    funbind: fundecl list   
+}
 
-type environment = 
-    {localvars: (vname * tp) list; 
-     funbind: fundecl list   
-    }
+let find_var (var: vname) (env: environment) =
+    let rec aux local_vars = 
+        match local_vars with
+        | [] -> failwith "Variable inconnue"
+        | tete::reste -> 
+            let (name, _) = tete in
+            if name = var
+            then tete
+            else aux reste
+    in aux (env.localvars)
+;;
 
+(* let rec tp_expr (expression: expr) (env: environment) =
+    match expression with
+    | Const(const) -> 
+        match const with
+        | BoolV(_) -> BoolT
+        | FloatV(_) -> FloatT
+        | IntV(_) -> IntT
+        | LitV(_) -> LitT
+        | StringV(_) -> StringT
+    | VarE(var) -> tp_expr (find_var var env) env
+    | BinOp(op, expr1, expr2) -> 
+    | CondE(expr1, expr2, expr3) -> 
+    | CallE(functionName, exprList) ->  *)
+;;
 
 let tp_prog (Prog (fundecls, fundefns)) = true