added example concurrent read write on struct

concurrency/read_struct_props/main.go

@@ -0,0 +1,83 @@
+package main
+
+import (
+	"time"
+
+	"github.com/davecgh/go-spew/spew"
+)
+
+// package shows if read/write concurrently via struct
+
+type Person struct {
+	Name   string
+	Age    uint32
+	Hobbit string
+}
+
+func (p *Person) generateAge() {
+	// mock read
+	for {
+		n := p.Name
+		spew.Dump(n)
+	}
+
+}
+
+func (p *Person) generateHobbit() {
+	// mock read
+	for {
+		n := p.Name
+		spew.Dump(n)
+	}
+
+}
+
+func (p *Person) mockWrite1() {
+	for {
+		p.Name = "Nmae1"
+	}
+}
+
+func (p *Person) mockWrite2() {
+	for {
+		p.Name = "Nmae2"
+	}
+}
+
+var m = map[string]int{"a": 1}
+
+func main() {
+	p := &Person{Name: "James"}
+	go p.generateAge()
+	go p.generateHobbit()
+	go p.mockWrite1()
+	go p.mockWrite2()
+	// SimulateConcurrentReadWriteMap()
+	time.Sleep(2 * time.Second)
+}
+
+func SimulateConcurrentReadWriteMap() {
+	// Concurrent read is ok, but write is not
+	go Read()
+	go Write()
+	time.Sleep(6 * time.Second)
+}
+
+func Read() {
+	for {
+		read()
+	}
+}
+
+func Write() {
+	for {
+		write()
+	}
+}
+func read() {
+	_ = m["a"]
+}
+
+func write() {
+	m["b"] = 2
+}