diff --git a/regression/test060.lama b/regression/test060.lama
index 82b131056..7b4069731 100644
--- a/regression/test060.lama
+++ b/regression/test060.lama
@@ -13,7 +13,7 @@ fun f (l) {
 local x = read ();
 
 write (f ({}));
-write (f ({1}));
+write (f (1:{}));
 write (f ({1, 1}));
 write (f ({1, 1, 1}));
 write (f ({1, 2, 1}))
diff --git a/regression/test092.lama b/regression/test092.lama
index 2b85c8504..3d4495b8a 100644
--- a/regression/test092.lama
+++ b/regression/test092.lama
@@ -13,7 +13,7 @@ fun f (l) {
 local x = read ();
 
 write (f ({}));
-write (f ({1}));
+write (f (1:{}));
 write (f ({1, 1}));
 write (f ({1, 1, 1}));
 write (f ({1, 2, 1}))
diff --git a/src/Language.ml b/src/Language.ml
index 77547faac..64a8b6907 100644
--- a/src/Language.ml
+++ b/src/Language.ml
@@ -312,8 +312,8 @@ module Pattern =
       | t:UIDENT ps:(-"(" !(Util.list)[parse] -")")? {Sexp (t, match ps with None -> [] | Some ps -> ps)}
       | "[" ps:(!(Util.list0)[parse]) "]"            {Array ps}
       | "{" ps:(!(Util.list0)[parse]) "}"            {match ps with
-                                                      | [] -> UnBoxed
-                                                      | _  -> List.fold_right (fun x acc -> Sexp ("cons", [x; acc])) ps UnBoxed
+                                                      | [] -> Const 0
+                                                      | _  -> List.fold_right (fun x acc -> Sexp ("cons", [x; acc])) ps (Const 0)
                                                      }
       | l:$ x:LIDENT y:(-"@" parse)?                 {Loc.attach x l#coord; match y with None -> Named (x, Wildcard) | Some y -> Named (x, y)}
       | s:("-")? c:DECIMAL                           {Const (match s with None -> c | _ -> ~-c)}
@@ -709,10 +709,6 @@ module Expr =
             let name = infix_name s in Loc.attach name l#coord; ignore atr (Var name)
           )
       }
-      (*
-      | l:$ %"fun" "(" args:!(Util.list0)[ostap (l:$ x:LIDENT {Loc.attach x l#coord; x})] ")"
-               "{" body:scope[infix][Weak] "}"=> {notRef atr} :: (not_a_reference l) => {ignore atr (Lambda (args, body))}
-       *)
       | l:$ %"fun" "(" args:!(Util.list0)[Pattern.parse] ")"
            "{" body:scope[infix][Weak] "}"=> {notRef atr} :: (not_a_reference l) => {
           let args, body =
diff --git a/src/SM.ml b/src/SM.ml
index 652524357..690530551 100644
--- a/src/SM.ml
+++ b/src/SM.ml
@@ -101,9 +101,19 @@ let rec eval env (((cstack, stack, glob, loc, i, o) as conf) : config) = functio
    Printf.eprintf "   insn=%s\n" (show_insn insn);
    Printf.eprintf "   stack=%s\n" (show(list) (show(value)) stack);
    Printf.eprintf "end\n";
-   *)
+    *)
    (match insn with
     | PUBLIC _ | EXTERN _     -> eval env conf prg'
+    | BINOP  "=="             -> let y::x::stack' = stack in
+                                 let z =
+                                   match x, y with
+                                   | Value.Int _, Value.Int _ -> Value.of_int @@ Expr.to_func "==" (Value.to_int x) (Value.to_int y)
+                                   | Value.Int _, _ | _, Value.Int _ -> Value.of_int 0
+                                   | _ -> failwith "unexpected operands in comparison: %s vs. %s\n"
+                                            (show(Value.t) (fun _ -> "<not supported>") (fun _ -> "<not supported>") x)
+                                            (show(Value.t) (fun _ -> "<not supported>") (fun _ -> "<not supported>") y)
+                                 in
+                                 eval env (cstack, z :: stack', glob, loc, i, o) prg'
     | BINOP  op               -> let y::x::stack' = stack in eval env (cstack, (Value.of_int @@ Expr.to_func op (Value.to_int x) (Value.to_int y)) :: stack', glob, loc, i, o) prg'
     | CONST n                 -> eval env (cstack, (Value.of_int n)::stack, glob, loc, i, o) prg'
     | STRING s                -> eval env (cstack, (Value.of_string @@ Bytes.of_string s)::stack, glob, loc, i, o) prg'
diff --git a/src/version.ml b/src/version.ml
index 3640c3944..22db40b80 100644
--- a/src/version.ml
+++ b/src/version.ml
@@ -1 +1 @@
-let version = "Version 1.00, fe5a9321, Sun Feb 23 01:48:49 2020 +0300"
+let version = "Version 1.00, 3e2c87d4, Sun Feb 23 22:15:27 2020 +0300"
diff --git a/stdlib/List.lama b/stdlib/List.lama
index 0804522f5..c2dc5143f 100644
--- a/stdlib/List.lama
+++ b/stdlib/List.lama
@@ -79,13 +79,13 @@ public fun flatten (l) {
 
   fun append (x) {
     local new = x : {};
-    
+
     curr [0][1] := new;
     curr [0] := new    
   }
-
+  
   iter (fun (x) {iter (append, x)}, l);
-
+  
   res [1]
 }
 
diff --git a/stdlib/regression/test07.lama b/stdlib/regression/test07.lama
index e637cda5a..b303630c7 100644
--- a/stdlib/regression/test07.lama
+++ b/stdlib/regression/test07.lama
@@ -3,11 +3,11 @@ import Collection;
 local a = {1, 2, 3}, b = {1, 2, 3}, t = emptyHashTab ();
 
 t := addHashTab (t, a, 100);
-validateColl ();
+validateColl (t);
 printf ("HashTab internal structure: %s\n", t.string);
 
 t := addHashTab (t, b, 200);
-validateColl ();
+validateColl (t);
 printf ("HashTab internal structure: %s\n", t.string);
 
 printf ("Searching: %s\n", findHashTab (t, a).string);