diff --git a/SLS_C/src/builtin.c b/SLS_C/src/builtin.c
index 22231fc..24f1b1c 100644
--- a/SLS_C/src/builtin.c
+++ b/SLS_C/src/builtin.c
@@ -1608,8 +1608,10 @@ Boolean builtin_if(InterpreterState *interpreter_state) {
 }
 
 Boolean builtin_lambda(InterpreterState *interpreter_state) {
-    (void)interpreter_state;
-    return FALSE;
+    if (interpreter_state->stack == NULL) return FALSE;
+    if (interpreter_state->stack->type != STACK_TOKEN_STRING) return FALSE;
+    interpreter_state->stack->type = STACK_CODE_BLOCK;
+    return TRUE;
 }
 
 Boolean builtin_ln(InterpreterState *interpreter_state) {
diff --git a/SLS_C/src/repl.c b/SLS_C/src/repl.c
index 88be976..2d0ea96 100644
--- a/SLS_C/src/repl.c
+++ b/SLS_C/src/repl.c
@@ -65,6 +65,9 @@ void print_top_of_stack(InterpreterState *interpreter_state) {
     case STACK_TOKEN_STRING:
         printf("#0: <TOKEN STRING>\n");
         break;
+    case STACK_CODE_BLOCK:
+        printf("#0: <CODE BLOCK>\n");
+        break;
     }
 }