后端程序员之路 53、A Tour of Go-3

#method
    - Methods
        - Go does not have classes. However, you can define methods on types.
        - func (f MyFloat) Abs() float64 {
    - Interfaces
        - type Abser interface { Abs() float64 }
        - One of the most ubiquitous interfaces is Stringer defined by the fmt package.
        - Go programs express error state with error values.
        - The io package specifies the io.Reader interface, which represents the read end of a stream of data.
        - Package image defines the Image interface

# concurrency
    - Goroutines - go say("world")
    - Channels
        - Channels are a typed conduit through which you can send and receive values with the channel operator, <-.
        - ch := make(chan int)
        - ch <- v    // Send v to channel ch.
        - v := <-ch  // Receive from ch, and assign value to v.
        - Buffered Channels - ch := make(chan int, 100)
    - Select
        - The select statement lets a goroutine wait on multiple communication operations.
        - The default case in a select is run if no other case is ready.
        - sync.Mutex
            - mux sync.Mutex
            - c.mux.Lock()
            - defer c.mux.Unlock()

A Tour of Go
https://tour.golang.org/list