JPathExpr     *JSONPath   `parser:"| @@"`
	ListExpr      *ListExpr   `parser:"| @@"`
	SubExpression *Expression `parser:"| \"(\" @@ \")\""`
	// Include function expressions here.
	FuncCall *FuncExpr `parser:"| @@"`
}

// FuncExpr represents a function call
type FuncExpr struct {
	SFunc     *SimpleArgFunc `parser:"  @@"`
	Count     *CountFunc     `parser:"| @@"`