Enabled user-defined constant constructors in expressions.

src/parser/pascaligo/AST.ml

@@ -597,7 +597,7 @@ and nil = kwd_nil
 and constr_expr =
   SomeApp   of (c_Some * arguments) reg
 | NoneExpr  of none_expr
-| ConstrApp of (constr * arguments) reg
+| ConstrApp of (constr * arguments option) reg
 
 and record_expr = field_assign reg injection reg
 

src/parser/pascaligo/AST.mli

@@ -581,7 +581,7 @@ and nil = kwd_nil
 and constr_expr =
   SomeApp   of (c_Some * arguments) reg
 | NoneExpr  of none_expr
-| ConstrApp of (constr * arguments) reg
+| ConstrApp of (constr * arguments option) reg
 
 and record_expr = field_assign reg injection reg
 

src/parser/pascaligo/Parser.mly

@@ -956,7 +956,10 @@ core_expr:
 | projection       { EProj $1                     }
 | Constr arguments {
     let region = cover $1.region $2.region in
-    EConstr (ConstrApp {region; value = $1,$2})
+    EConstr (ConstrApp {region; value = $1, Some $2})
+  }
+| Constr {
+    EConstr (ConstrApp {region=$1.region; value = $1,None})
   }
 | C_Some arguments {
     let region = cover $1 $2.region in

src/parser/pascaligo/ParserLog.ml

@@ -648,7 +648,9 @@ and print_fun_call {value; _} =
 and print_constr_app {value; _} =
   let constr, arguments = value in
   print_constr    constr;
-  print_tuple_inj arguments
+  match arguments with
+    None -> ()
+  | Some args -> print_tuple_inj args
 
 and print_some_app {value; _} =
   let c_Some, arguments = value in

src/simplify/pascaligo.ml

@@ -416,11 +416,14 @@ let rec simpl_expression (t:Raw.expr) : expr result =
   | EProj p -> simpl_projection p
   | EConstr (ConstrApp c) -> (
       let ((c, args) , loc) = r_split c in
-      let (args , args_loc) = r_split args in
-      let%bind arg =
-        simpl_tuple_expression ~loc:args_loc
-        @@ npseq_to_list args.inside in
-      return @@ e_constructor ~loc c.value arg
+      match args with
+        None -> simpl_tuple_expression []
+      | Some args ->
+          let args, args_loc = r_split args in
+          let%bind arg =
+            simpl_tuple_expression ~loc:args_loc
+            @@ npseq_to_list args.inside in
+          return @@ e_constructor ~loc c.value arg
     )
   | EConstr (SomeApp a) ->
       let ((_, args) , loc) = r_split a in