Find centralized, trusted content and collaborate around the technologies you use most.
Teams
Q&A for work
Connect and share knowledge within a single location that is structured and easy to search.
这是新数据类型的定义:
data Total a = Total a :+: Total a |...
:+: 在这种类型定义中是什么意思?
它是一个以中缀形式编写的数据构造函数。如果运算符以 . 开头,则可以将其用作构造函数:。
: