run arrays primes var auto 程序 pointer ase tex

# flowcontrol
- for
- for i := 0; i < 10; i++ {
- for ; sum < 1000; {
- For is Go‘s "while" - for sum < 1000 {
- Forever - for {
- if
- if x < 0 {
- } else {
- if v := math.Pow(x, n); v < lim {
- switch
- switch os := runtime.GOOS; os {

- A case body breaks automatically
- fallthrough
- defer
- A defer statement defers the execution of a function until the surrounding function returns.
- defer fmt.Println("world")
- Deferred function calls are pushed onto a stack(LIFO)

# moretypes
- Pointers - var p *int

- Structs
- type Vertex struct {
- v := Vertex{1, 2}
- Arrays
- var a [10]int
- primes := [6]int{2, 3, 5, 7, 11, 13}
- Slices
- var s []int = primes[1:4]
- A slice does not store any data, it just describes a section of an underlying array.
- q := []int{2, 3, 5, 7, 11, 13}
- var a [10]int -> a[0:10] == a[:10] == a[0:] == a[:]
- printSlice fmt.Printf("len=%d cap=%d %v\n", len(s), cap(s), s)
- The zero value of a slice is nil.
- a := make([]int, 5) // len(a)=5 || b := make([]int, 0, 5) // len(b)=0, cap(b)=5
- Slices of slices - board := [][]string{
- for i, v := range pow { || for i := range pow { || for _, value := range pow {
- Maps
- m[key] = elem
- elem = m[key]
- delete(m, key)
- elem, ok = m[key]
- Function values
- hypot := func(x, y float64) float64 {
- return func(x int) int {

後端程序員之路 52、A Tour of Go-2