go指针逃逸对结构体元素集合法(增法)

例子1

package main

import (
   "awesomeProject/logger"
   "fmt"
   "github.com/opencontainers/runtime-tools/filepath"
   "os"
)

type Goods struct {
   ID    uint
   MonTs string
}

func Mkfile() {
   filepaht := filepath.Join(os.TempDir(), "nginx")

   if _, err := os.Stat(filepaht); os.IsNotExist(err) {
      err = os.MkdirAll(filepaht, 0644)
      if err != nil {
         logger.DefaultLogger.Errorf("%v", err)
      }

   }
}
func NewGoods(id uint) *Goods {
   return &Goods{ID: id}

}
func (g *Goods) SetMontsAdd(m string) *Goods {
   g.MonTs = m
   return g

}

func main() {

   g := NewGoods(100).SetMontsAdd("TE")

   fmt.Println(g) //{100 TE}

}

例子2
package main

import (
   "awesomeProject/logger"
   "fmt"
   "github.com/opencontainers/runtime-tools/filepath"
   "os"
)

type Goods struct {
   ID    uint
   MonTs string
}

func Mkfile() {
   filepaht := filepath.Join(os.TempDir(), "nginx")

   if _, err := os.Stat(filepaht); os.IsNotExist(err) {
      err = os.MkdirAll(filepaht, 0644)
      if err != nil {
         logger.DefaultLogger.Errorf("%v", err)
      }

   }
}
func (g *Goods) SetId(id uint) *Goods {
   g.ID = id
   return g

}
func (g *Goods) SetMonts(m string) *Goods {
   g.MonTs = m
   fmt.Printf("%T\n", g)
   return g

}

func main() {

   var g Goods   //或者var g = &Goods{}

   g.SetId(100).SetMonts("test")
   fmt.Println(g)    //{100 test}

}


例子3

package main

import (
   "awesomeProject/logger"
   "fmt"
   "github.com/opencontainers/runtime-tools/filepath"
   "os"
)

type Goods struct {
   ID    uint
   MonTs string
}

func Mkfile() {
   filepaht := filepath.Join(os.TempDir(), "nginx")

   if _, err := os.Stat(filepaht); os.IsNotExist(err) {
      err = os.MkdirAll(filepaht, 0644)
      if err != nil {
         logger.DefaultLogger.Errorf("%v", err)
      }

   }
}
func (g *Goods) SetId(id uint) uint {
   g.ID = id
   return g.ID

}
func (g *Goods) SetMonts(m string) string {
   g.MonTs = m

   return g.MonTs

}

func main() {

   var g *Goods //（改为var g Goods  或者var g = &Goods{}）

   g.SetId(100)
   g.SetMonts("test")
   fmt.Println(g)

}    // 用var g *Goods 报错 runtime error: invalid memory address or nil pointer dereference