diff --git a/src/spectator/mocks/generic_arguments.cr b/src/spectator/mocks/generic_arguments.cr
index 0da404c..7ac7db5 100644
--- a/src/spectator/mocks/generic_arguments.cr
+++ b/src/spectator/mocks/generic_arguments.cr
@@ -16,7 +16,7 @@ module Spectator::Mocks
       dispatcher.call(*@args, **@opts)
     end
 
-    def ===(other : GenericArguments(U, NU)) : Bool forall U, NU
+    def ===(other) : Bool
       return false unless @args === other.args
       return false unless @opts.size === other.opts.size