一、for循环
 
package mainimport (myerror "day02/errors""errors""fmt"
)func main() {for i := 0; i < 100; i++ {fmt.Println("第一种:", i)}i := 0for i < 10 {i++fmt.Println("第二种:", i)}for {i++fmt.Println("第三种:", i)if i > 20 {break}}names := map[string]int{"John":   100,"Paul":   200,"George": 300,"Ringo":  400,}for k, v := range names {fmt.Println("第四种:", k, v)}err := errors.New("hello error")fmt.Println(err)err02 := myerror.New("hello error")fmt.Println(err02)
}
 
二、包构建
 
go build main.go
 
三、包冲突
 
- 1、创建一个和系统重名的包
 
 
 
package errors
func New(msg string) string {return msg
}
 
 
package mainimport (myerror "day02/errors""errors""fmt"
)func main() {err := errors.New("hello error")fmt.Println(err)err02 := myerror.New("hello error")fmt.Println(err02)
}