syncmap.go

package main

import "fmt"

type syncMap chan map[string]int

func newSyncMap() syncMap {
	m := make(map[string]int)
	sm := make(syncMap, 1)
	sm <- m
	return sm
}

func (sm syncMap) get(key string) (int, bool) {
	m := <-sm
	v, ok := m[key]
	sm <- m
	return v, ok
}

func (sm syncMap) set(key string, val int) {
	m := <-sm
	m[key] = val
	sm <- m
}

func main() {
	m := newSyncMap()
	m.set("foo", 1)
	m.set("bar", 2)

	foo, ok := m.get("foo")
	fmt.Println(foo, ok)

	bar, ok := m.get("bar")
	fmt.Println(bar, ok)

	baz, ok := m.get("baz")
	fmt.Println(baz, ok)
}