internal

var (
	ErrDivisionByZero      = errors.New("除以零错误")
	ErrUndefinedVariable   = errors.New("未定义的变量")
	ErrUnsupportedOperator = errors.New("不支持的运算符")
	ErrInvalidExpression   = errors.New("无效的表达式")
	ErrInvalidArgument     = errors.New("无效的参数")
	ErrMaxRecursionDepth   = errors.New("超过最大递归深度")
	ErrExecutionTimeout    = errors.New("执行超时")
)