map _ golang

Maps are Go's built-in associative data type(sometimes called hashes or dits in other languages)

package main

import (
    "fmt"
)

func main() {

    m := make(map[string]int)

    m["k1"] = 7
    m["k2"] = 13

    fmt.Println("map :", m)

    v1 := m["k1"]
    fmt.Println("v1 :", v1)

    fmt.Println("len : ", len(m))

    delete(m, "k2")
    fmt.Println("map:", m)

    a, prs := m["k2"]
    fmt.Println("prs:", prs, a)

    n := map[string]int{"foo": 1, "bar": 2}
    fmt.Println("map:", n)
}

map : map[k1:7 k2:13]
v1 : 7
len :  2
map: map[k1:7]
prs: false 0
map: map[foo:1 bar:2]

　　总结 :

　　　　1 : 奇怪的构造方法 m := make(map[string]int)

　　　　2 : .......