use -literal for top level exprs

diff --git a/lib/SQL/Abstract.pm b/lib/SQL/Abstract.pm
index 9ce3d1b..232b290 100644 (file)
--- a/lib/SQL/Abstract.pm
+++ b/lib/SQL/Abstract.pm
@@ -576,6 +576,9 @@ sub _expand_expr {
     }
     return { '-'.$logic => \@res };
   }
+  if (my $literal = is_literal_value($expr)) {
+    return +{ -literal => $literal };
+  }
   return $expr;
 }