The set_literalizer extension should no longer be used, as Sequel now supports Set values by default. For backwards compatibility the set_literalizer extension will treat a set that contains only 2 element arrays as a condition specifier (matching the behavior for arrays where all elements are 2 element arrays). This is not compatible with Sequel’s current default behavior. If you are relying on this behavior, it is recommended you convert the set to an array.
Related module: Sequel::Dataset::SetLiteralizer