1 files changed, 8 insertions, 0 deletions
diff --git a/parse.y b/parse.y
index 2d82b7b61c..bfc8cd9823 100644
--- a/parse.y
+++ b/parse.y
@@ -2621,6 +2621,14 @@ primary		: literal
 			$$ = dispatch2(unary, ripper_intern("not"), $3);
 		    %*/
 		    }
+		| keyword_not '(' rparen
+		    {
+		    /*%%%*/
+			$$ = NEW_LIT(Qtrue);
+		    /*%
+			$$ = dispatch2(unary, ripper_intern("not"), Qnil);
+		    %*/
+		    }
 		| operation brace_block
 		    {
 		    /*%%%*/