code: function getSquashPolicy(config, isOptional) {
        var squash = config.squash;
        if (!isOptional || squash === false) return false;
        if (!isDefined(squash) || squash == null) return defaultSquashPolicy;
        if (squash === true || isString(squash)) return squash;
        throw new Error("Invalid squash policy: '" + squash + "'. Valid policies: false, true, or arbitrary string");
      }
docs: returns false, true, or the squash value to indicate the "default parameter url squash policy".