public JsBlock ParseExpression(JsSettings settings)
{
// we need to make sure the settings object has the expression source mode property set,
// but let's not modify the settings object passed in. So clone it, set the property on the
// clone, and use that object for parsing.
settings = settings == null ? new JsSettings() : settings.Clone();
settings.SourceMode = JsSourceMode.Expression;
return Parse(settings);
}