Pass anonymous function to simplification principle

Anonymous functions

** explain ：** Functions without names are anonymous functions .

(x:Int) => { The body of the function }

x： Represents the input parameter type ;Int： Represents the input parameter type ; The body of the function ： Represents specific code logic

Pass anonymous functions to the simplicity principle ：

1. The type of parameter can be omitted , Will automatically deduce according to the formal parameters

2. After type omission , It turns out that there's only one parameter , The parentheses can be omitted ;

3. Other situations ： There are no parameters and parameters beyond 1 You can never omit the parentheses .

4. If anonymous function has only one line , The braces can also be omitted

5. If the parameter appears only once , Then the parameters are omitted and the following parameters can be used _ Instead of