diff --git a/modules/mol/base/src/impl/query_ast.hh b/modules/mol/base/src/impl/query_ast.hh
index 2f46ec4996f8fad405f024f265aa321acd002ab8..6105213939f0f64fc63ce07c82e21b7004a862ff 100644
--- a/modules/mol/base/src/impl/query_ast.hh
+++ b/modules/mol/base/src/impl/query_ast.hh
@@ -68,7 +68,7 @@ class DLLEXPORT_OST_MOL StringOrRegexParam {
   String s_;
 };
 
-typedef boost::variant<int, float, WithinParam, StringOrRegexParam> ParamType;
+typedef boost::variant<int, Real, WithinParam, StringOrRegexParam> ParamType;
 
 // AST node, used internally for building the AST tree.
 class DLLEXPORT_OST_MOL Node {