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Foo.Bar.Baz()
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Functional Options ãã¿ãŒã³ã䜿çšããŠããªã (#11)
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API ã«é©ããæ¹æ³ã§ãªãã·ã§ã³ã䟿å©ã«åŠçããã«ã¯ãFunctional Options ãã¿ãŒã³ã䜿çšããŸãããã
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- åãªãã·ã§ã³ã¯åãåã
type Option func(options *options)
ãšã©ãŒãè¿ãé¢æ°ã§ããããšãã°ãWithPort
ã¯ããŒããè¡šãint
åŒæ°ãåãåããoptions
æ§é äœã®æŽæ°æ¹æ³ãè¡šãOption
åãè¿ããŸãã
type options struct {
port *int
}
type Option func(options *options) error
func WithPort(port int) Option {
return func(options *options) error {
if port < 0 {
return errors.New("port should be positive")
}
options.port = &port
return nil
}
}
func NewServer(addr string, opts ...Option) ( *http.Server, error) {
var options options
for _, opt := range opts {
err := opt(&options)
if err != nil {
return nil, err
}
}
// ãã®æ®µéã§ãoptions æ§é äœãæ§ç¯ãããæ§æãå«ãŸããŸãã
// ãããã£ãŠãããŒãèšå®ã«é¢é£ããããžãã¯ãå®è£
ã§ããŸãã
var port int
if options.port == nil {
port = defaultHTTPPort
} else {
if *options.port == 0 {
port = randomPort()
} else {
port = *options.port
}
}
// ...
}
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func readFiles(ch <-chan string) error {
for path := range ch {
file, err := os.Open(path)
if err != nil {
return err
}
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// ãã¡ã€ã«ã®åŠçããã
}
return nil
}
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func readFiles(ch <-chan string) error {
for path := range ch {
if err := readFile(path); err != nil {
return err
}
}
return nil
}
func readFile(path string) error {
file, err := os.Open(path)
if err != nil {
return err
}
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return nil
}
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s := "hêllo"
for i := range s {
fmt.Printf("position %d: %c\n", i, s[i])
}
fmt.Printf("len=%d\n", len(s))
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}
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}
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}
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ã¯å¥ã® n
ãã€ãã®ããã®ã¹ããŒã¹ãä¿èšŒããã¡ãœãã Grow(n int)
ãæã£ãŠããŸãã
func concat(values []string) string {
total := 0
for i := 0; i < len(values); i++ {
total += len(values[i])
}
sb := strings.Builder{}
sb.Grow(total) (2)
for _, value := range values {
_, _ = sb.WriteString(value)
}
return sb.String()
}
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BenchmarkConcatV1-4 16 72291485 ns/op
BenchmarkConcatV2-4 1188 878962 ns/op
BenchmarkConcatV3-4 5922 190340 ns/op
ã芧ã®ãšãããææ°ããŒãžã§ã³ãæãå¹ççã§ãV1 ãã 99% ãV2 ãã 78% é«éã§ãã
strings.Builder
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- ã¬ã·ãŒããŒãã
time.Time
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int
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ååä»ãçµæãã©ã¡ãŒã¿ãç¶æ³ã«ãã£ãŠã¯åœ¹ç«ã€çç±ã«ã€ããŠèª¬æããŸããã ãã ãããããã¯ãŒãå€ã«åæåããããããååã«æ³šæããªããšã軜埮ãªãã°ãçºçããå¯èœæ§ããããŸããããšãã°ããã®ã³ãŒãã¯ã©ããééã£ãŠããã§ããããã
func (l loc) getCoordinates(ctx context.Context, address string) (
lat, lng float32, err error) {
isValid := l.validateAddress(address) (1)
if !isValid {
return 0, 0, errors.New("invalid address")
}
if ctx.Err() != nil { (2)
return 0, 0, err
}
// 座æšãååŸããŠè¿ã
}
äžç¥ããã ãã§ã¯ãšã©ãŒã¯æããã§ã¯ãªããããããŸãããif ctx.Err() != nil
ã¹ã³ãŒãã§è¿ããããšã©ãŒã¯ err
ã§ããããããerr
å€æ°ã«ã¯å€ãå²ãåœãŠãŠããŸãããerror
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nil ã¬ã·ãŒããŒãè¿ã (#45)
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ãš incrementCounter
ãåŒã³åºããŸãã
const (
StatusSuccess = "success"
StatusErrorFoo = "error_foo"
StatusErrorBar = "error_bar"
)
func f() error {
var status string
defer notify(status)
defer incrementCounter(status)
if err := foo(); err != nil {
status = StatusErrorFoo
return err
}
if err := bar(); err != nil {
status = StatusErrorBar
return err
}
status = StatusSuccess
return nil
}
ãããã«ãnotify(status)
ãš incrementCounter(status)
ã defer
é¢æ°ãšããŠåŒã³åºããŠããŸãããããã£ãŠãGoèšèªã¯ãdefer ã䜿çšãã段é㧠f
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defer
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func f() error {
var status string
defer notify(&status)
defer incrementCounter(&status)
// é¢æ°ã®ãã以å€ã®éšåã¯å€æŽãªã
}
defer
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§ããå¿åé¢æ°å€ïŒã defer
æãšããŠåŒã³åºãããšã§ãã
func f() error {
var status string
defer func() {
notify(status)
incrementCounter(status)
}()
// é¢æ°ã®ãã以å€ã®éšåã¯å€æŽãªã
}
ããã§ã¯ãnotify
ãš incrementCounter
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ã incrementCounter
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panic
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é ã®äŸåé¢ä¿ã®èªã¿èŸŒã¿ã«å€±æããå Žåãªã©ã§ãã
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Go Context ã«å¯Ÿãã誀解 (#60)
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Go Context ã¯ãGoèšèªã®äžŠè¡åŠçã®åºç€ã®äžéšã§ããããŸãã Context ã䜿çšãããšããããã©ã€ã³ãããŒãšå€ã®ãªã¹ããä¿æã§ããŸãã
https://pkg.go.dev/context
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Go Context ã®æåŸã®äœ¿çšäŸã¯ãããŒãšå€ã®ãªã¹ããéã¶ããšã§ãã Context ã«ããŒãšå€ã®ãªã¹ããå«ããæå³ã¯äœã§ãããããGo Context ã¯æ±çšçã§ããããã䜿çšäŸã¯ç¡éã«ãããŸãã
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Context ãäŒæããéã«ã¯ãContext ããã£ã³ã»ã«ã§ããæ¡ä»¶ãç解ããããšãéèŠã§ããããšãã°ãã¬ã¹ãã³ã¹ãéä¿¡ãããéã« HTTP ãã³ãã©ã Context ããã£ã³ã»ã«ãããšããªã©ã§ãã
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func handler(w http.ResponseWriter, r *http.Request) {
response, err := doSomeTask(r.Context(), r)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
go func() {
err := publish(r.Context(), response)
// err ã®åŠçããã
}()
writeResponse(response)
}
ãã®ã³ãŒãã®äœãåé¡ãªã®ã§ãããããHTTP ãªã¯ãšã¹ãã«ä»ããã Context ã¯ãããŸããŸãªç¶æ³ã§ãã£ã³ã»ã«ãããå¯èœæ§ãããããšãç¥ã£ãŠããå¿ èŠããããŸãã
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- ã¯ã©ã€ã¢ã³ãã«ã¬ã¹ãã³ã¹ãæžãæ»ããããšã
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ãªãŒã¯ãé¿ããããšã¯ããŽã«ãŒãã³ãéå§ããããã³ã«ãæçµçã«åæ¢ããå¿ èŠãããããšãæå³ããŸãã
ãŽã«ãŒãã³ã¯ç°¡åã«è¡ãããšãã§ããŸããéåžžã«ç°¡åã§ãããããæ°ãããŽã«ãŒãã³ããã€åæ¢ãããã«ã€ããŠã®èšç»ãå¿ ãããç«ãŠãŠããªãå¯èœæ§ãããããªãŒã¯ã«ã€ãªããããšããããŸãããŽã«ãŒãã³ããã€åæ¢ããã°ãããããããªãã®ã¯ãGoèšèªã§ããããèšèšäžã®åé¡ã§ããã䞊è¡åŠçã«ããããã¹ã§ãã
å ·äœçãªäŸã«ã€ããŠèª¬æããŸããããå€éšèšå®ïŒããŒã¿ããŒã¹æ¥ç¶ãªã©ã䜿çšãããã®ãªã©ïŒãç£èŠããå¿ èŠãããã¢ããªã±ãŒã·ã§ã³ãèšèšããŸãããŸãã次ã®ãããªå®è£ ãããŠã¿ãŸãã
func main() {
newWatcher()
// ã¢ããªã±ãŒã·ã§ã³ãå®è¡ãã
}
type watcher struct { /* ããã€ãã®ãªãœãŒã¹ */ }
func newWatcher() {
w := watcher{}
go w.watch() // å€éšèšå®ãç£èŠãããŽã«ãŒãã³ãäœæãã
}
ãã®ã³ãŒãã®åé¡ã¯ãã¡ã€ã³ã®ãŽã«ãŒãã³ãçµäºãããšïŒãããã OS ã·ã°ãã«ãŸãã¯æéã®ã¯ãŒã¯ããŒãã®ããïŒãã¢ããªã±ãŒã·ã§ã³ãåæ¢ããŠããŸãããšã§ãããããã£ãŠããŠã©ããã£ãŒã«ãã£ãŠäœæããããªãœãŒã¹ã¯æ£åžžã«éããããŸããããããé²ãã«ã¯ã©ãããã°ããã§ããããã
1 ã€ã®æ¹æ³ãšããŠã¯ãmain ãæ»ã£ããšãã«ãã£ã³ã»ã«ããã Context ã newWatcher ã«æž¡ãããšãæããããŸãã
func main() {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
newWatcher(ctx)
// ã¢ããªã±ãŒã·ã§ã³ãå®è¡ãã
}
func newWatcher(ctx context.Context) {
w := watcher{}
go w.watch(ctx)
}
äœæãã Context ã watch ã¡ãœããã«äŒæããŸããContext ããã£ã³ã»ã«ããããšããŠã©ããã£ãŒæ§é äœã¯ãã®ãªãœãŒã¹ãéããŸããããããwatch ããããè¡ãæéã確å®ã«ãããšã¯ãããŸãããããã¯èšèšäžã®æ¬ é¥ã§ãã
åé¡ã¯ããŽã«ãŒãã³ãåæ¢ããå¿ èŠãããããšãäŒããããã«ã·ã°ãã«ã䜿çšããããšã§ãããªãœãŒã¹ãéãããããŸã§ã芪ã®ãŽã«ãŒãã³ããããã¯ããŸããã§ããããããªããªãããã«ããŸãããã
func main() {
w := newWatcher()
defer w.close()
// ã¢ããªã±ãŒã·ã§ã³ãå®è¡ãã
}
func newWatcher() watcher {
w := watcher{}
go w.watch()
return w
}
func (w watcher) close() {
// ãªãœãŒã¹ãéãã
}
ãªãœãŒã¹ãéããæéã«ãªã£ãããšã watcher
ã«éç¥ãã代ããã«ã defer
ã䜿çšããŠãã®ãclose
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ãŸãšãããšããŽã«ãŒãã³ã¯ä»ã®ãªãœãŒã¹ãšåæ§ãã¡ã¢ãªãä»ã®ãªãœãŒã¹ã解æŸããããã«æçµçã«éããå¿ èŠãããããšã«æ³šæããŠãã ããããŽã«ãŒãã³ããã€åæ¢ããããç¥ããã«éå§ããã®ã¯èšèšäžã®åé¡ã§ãããŽã«ãŒãã³ãéå§ããããšãã¯åžžã«ããã€åæ¢ãããã«ã€ããŠæ確ãªèšç»ãç«ãŠãå¿ èŠããããŸããæåŸã«ãªããŸãããããŽã«ãŒãã³ããªãœãŒã¹ãäœæãããã®æå¹æéãã¢ããªã±ãŒã·ã§ã³ã®åç¶æéã«ãã€ã³ããããŠããå Žåã¯ãã¢ããªã±ãŒã·ã§ã³ãçµäºããåã«ãã®ãŽã«ãŒãã³ãå®äºããã®ãåŸ ã£ãæ¹ããããã確å®ã§ããããããããšã§ããªãœãŒã¹ãééããªã解æŸã§ããŸãã
ãŽã«ãŒãã³ãšã«ãŒãå€æ°ã«æ³šæããªã (#63)
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ãã®ãã¹ã¯ Goã1.22 ããã¯æ°ã«ããå¿ èŠããããŸããïŒè©³çŽ°ïŒã
select
ãšãã£ãã«ã䜿çšããŠæ±ºå®çåäœãæåŸ
ãã (#64)
èŠçŽ
è€æ°ã®ãªãã·ã§ã³ãå¯èœãªå Žåãè€æ°ã®ãã£ãã«ã§ select
ãããšã±ãŒã¹ãã©ã³ãã ã«éžæãããããšãç解ãããšã䞊è¡åŠçã«ããã軜埮ãªãã°ã«ã€ãªããå¯èœæ§ã®ãã誀ã£ãä»®å®ãç«ãŠãããšããªããªããŸãã
Go éçºè ããã£ãã«ãæäœãããšãã«ãããã¡ãªééãã® 1 ã€ã¯ãselect ãè€æ°ã®ãã£ãã«ã§ã©ã®ããã«åäœãããã«ã€ããŠèª€ã£ãç解ãããããšã§ãã
ããšãã°ã次ã®å ŽåãèããŠã¿ãŸãããïŒ disconnectCh
ã¯ãããã¡ãªããã£ãã«ã§ãïŒã
go func() {
for i := 0; i < 10; i++ {
messageCh <- i
}
disconnectCh <- struct{}{}
}()
for {
select {
case v := <-messageCh:
fmt.Println(v)
case <-disconnectCh:
fmt.Println("disconnection, return")
return
}
}
ãã®äŸãè€æ°åå®è¡ããå Žåãçµæã¯ã©ã³ãã ã«ãªããŸãã
ã©ãããããã 10 éã®ã¡ãã»ãŒãžãæ¶è²»ããã®ã§ã¯ãªãããã®ãã¡ã®æ°éã ããåä¿¡ããŸãããããã¯ãè€æ°ã®ãã£ãã«ãšäœµçšããå Žåã® select æã®ä»æ§ã«ãããã®ã§ãïŒhttps:// go.dev/ref/specïŒã
Quote
1 ã€ä»¥äžã®éä¿¡ãç¶è¡ã§ããå Žåãåäžã®æ¬äŒŒã©ã³ãã éžæã«ãã£ãŠãç¶è¡ã§ãã 1 ã€ã®éä¿¡ãéžæãããŸãã
æåã«äžèŽããã±ãŒã¹ãåªå ããã switch æãšã¯ç°ãªããselect æã¯è€æ°ã®ãªãã·ã§ã³ãå¯èœãªå Žåã«ã©ã³ãã ã«éžæããŸãã
ãã®åäœã¯æåã¯å¥åŠã«æãããããããŸãããããããããã¯ã¹ã¿ããŒã·ã§ã³ãé²ããšããçç±ããã£ãŠã®ããšã§ããæåã«éžæãããéä¿¡ããœãŒã¹ã®é åºã«åºã¥ããŠãããšããŸãããã®å Žåãéä¿¡é床ãéãããã«ãããšãã° 1 ã€ã®ãã£ãã«ããããåä¿¡ã§ããªããšããç¶æ³ã«é¥ãå¯èœæ§ããããŸãããããé²ãããã«ãGoèšèªã®èšèšè ã¯ã©ã³ãã éžæã䜿çšããããšã«ããŸããã
è€æ°ã®ãã£ãã«ã§ select
ã䜿çšããå Žåãè€æ°ã®ãªãã·ã§ã³ããããªãããœãŒã¹é åºã®æåã®ã±ãŒã¹ãèªåçã«åªå
ãããããã§ã¯ãªãããšã«æ³šæããå¿
èŠããããŸãã代ããã«ãGoèšèªã¯ã©ã³ãã ã«éžæãããããã©ã®ãªãã·ã§ã³ãéžæããããã¯ä¿èšŒãããŸããããã®åäœãå
æããã«ã¯ãåäžã®çç£è
ãŽã«ãŒãã³ã®å Žåããããã¡ãªãã®ãã£ãã«ãŸãã¯åäžã®ãã£ãã«ã䜿çšããããšãã§ããŸãã
éç¥ãã£ãã«ã䜿çšããŠããªã (#65)
èŠçŽ
chan struct{}
åã䜿çšããŠéç¥ãéä¿¡ããŸãããã
ãã£ãã«ã¯ãã·ã°ãã«ãä»ããŠãŽã«ãŒãã³éã§éä¿¡ããããã®ã¡ã«ããºã ã§ããã·ã°ãã«ã«ã¯ããŒã¿ãå«ãŸããŠãããã©ããã¯é¢ä¿ãããŸããã
å
·äœçãªäŸãèŠãŠã¿ãŸããããéä¿¡ã®åæãçºçãããã³ã«ãããéç¥ãããã£ãã«ãäœæããŸãã 1 ã€ã®æ¹æ³ãšããŠãããã chan bool
ãšããŠæ±ãããšãæããããŸãã
ããã§ããã®ãããªãã£ãã«ãæäŸãã API ãšå¯Ÿè©±ãããšããŸããããã¯çåœå€ã®ãã£ãã«ã§ãããããtrue
ãŸã㯠false
ã®ã¡ãã»ãŒãžãåä¿¡ã§ããŸããtrue
ãäœãäŒããŠãããã¯ããããæããã§ãããããããã false
ãšã¯äœãæå³ããã®ã§ãããããéä¿¡ãåæãããŠããªããšããããšã§ããããããã®å Žåãã©ããããã®é »åºŠã§ãã®ãããªã·ã°ãã«ãåä¿¡ããã®ã§ããããããããã¯åæ¥ç¶ãããšããããšã§ããããããããã false
ãåãåãããšãæåŸ
ãã¹ããªã®ã§ããããããããã true
ã¡ãã»ãŒãžãåãåãããšã ããæåŸ
ãã¹ãã§ãããã
ãã®å Žåãæ
å ±ãäŒããããã«ç¹å®ã®å€ã¯å¿
èŠãªãããšãæå³ããããŒã¿ã® ãªã ãã£ãã«ãå¿
èŠã«ãªããŸãããããåŠçããæ
£çšçãªæ¹æ³ã¯ã空ã®æ§é äœã®ãã£ãã«ââ chan struct{}
ââã䜿çšããããšã§ãã
nil ãã£ãã«ã䜿çšããŠããªã (#66)
èŠçŽ
nil ãã£ãã«ã䜿çšããããšã«ãã£ãŠãããšãã° select
æããã±ãŒã¹ã åé€ ã§ããããã䞊è¡åŠçãè¡ãéã®éå
·ã®äžã€ãšããŠäœ¿ããããã«ãªãã¹ãã§ãã
次ã®ã³ãŒãã«ãã£ãŠäœãè¡ãããã§ããããã
ch
㯠chan int
åã§ãããã£ãã«ã®ãŒãå€ã¯ nil ã§ããã®ã§ã ch
㯠nil
ã§ãããŽã«ãŒãã³ã¯ panic ãèµ·ãããŸããããã ããæ°žä¹
ã«ãããã¯ããŸãã
nil ãã£ãã«ã«ã¡ãã»ãŒãžãéä¿¡ããå Žåãåçã¯åãã§ãã以äžã®ãŽã«ãŒãã³ã¯æ°žä¹ ã«ãããã¯ããŸãã
ã§ã¯ãGoèšèªã nil ãã£ãã«ãšã®éã§ã¡ãã»ãŒãžã®éåä¿¡ãèš±å¯ããç®çã¯äœã§ãããããããšãã°ã2 ã€ã®ãã£ãã«ãããŒãžããæ £çšçãªæ¹æ³ãå®è£ ããã®ã«ã nil ãã£ãã«ã䜿çšããããšãã§ããŸãã
func merge(ch1, ch2 <-chan int) <-chan int {
ch := make(chan int, 1)
go func() {
for ch1 != nil || ch2 != nil { // æäœã§ãäžã€ã®ãã£ãã«ã nil ã§ãªããã°ç¶è¡ãã
select {
case v, open := <-ch1:
if !open {
ch1 = nil // éããã ch1 ã nil ãã£ãã«ã«å²ãåœãŠã
break
}
ch <- v
case v, open := <-ch2:
if !open {
ch2 = nil // éããã ch2 ã nil ãã£ãã«ã«å²ãåœãŠã
break
}
ch <- v
}
}
close(ch)
}()
return ch
}
ãã®æŽç·Žããã解決çã¯ãnil ãã£ãã«ãå©çšããŠãäœããã®æ¹æ³ã§ select
æãã 1 ã€ã®ã±ãŒã¹ã åé€ ããŸãã
nil ãã£ãã«ã¯ç¶æ³ã«ãã£ãŠã¯äŸ¿å©ã§ãããGo éçºè ã¯äžŠè¡åŠçãæ±ãéã«äœ¿ãããªããããã«ãªã£ãŠããã¹ãã§ãã
ãã£ãã«ã®å®¹éã«ã€ããŠå°æããŠãã (#67)
èŠçŽ
åé¡ãçºçããå Žåã¯ã䜿çšãããã£ãã«ã®åãæ éã«æ±ºå®ããŠãã ãããåæã匷åã«ä¿èšŒããŠãããã®ã¯ãããã¡ãªããã£ãã«ã®ã¿ã§ãã
ãããã¡ãããã£ãã«ä»¥å€ã®ãã£ãã«ã®å®¹éãæå®ããã«ã¯æ£åœãªçç±ãããã¹ãã§ãã
æååãã©ãŒãããã§èµ·ããåŸãå¯äœçšãå¿ããŠããŸãïŒ etcd ããŒã¿ç«¶åã®äŸãšãããããã¯ïŒ (#68)
èŠçŽ
æååã®æžåŒèšå®ãæ¢åã®é¢æ°ãåŒã³åºãå¯èœæ§ãããããšãèªèããããšã¯ããããããã¯ããã®ä»ã®ããŒã¿ç«¶åã®å¯èœæ§ã«æ³šæããããšãæå³ããŸãã
append
ã§ããŒã¿ç«¶åãèµ·ãããŠããŸã (#69)
èŠçŽ
append
ã®åŒã³åºãã¯å¿
ãããããŒã¿ç«¶åããªãããã§ã¯ãããŸãããããã«ãå
±æã¹ã©ã€ã¹äžã§åæã«äœ¿çšããŠã¯ãããŸããã
ã¹ã©ã€ã¹ãšãããã§ãã¥ãŒããã¯ã¹ãæ£ãã䜿çšããŠããªã (#70)
èŠçŽ
ã¹ã©ã€ã¹ãšãããã¯ãã€ã³ã¿ã§ããããšãèŠããŠãããšãå žåçãªããŒã¿ç«¶åãé²ãããšãã§ããŸãã
sync.WaitGroup
ãæ£ãã䜿çšããŠããªã (#71)
èŠçŽ
sync.WaitGroup
ãæ£ãã䜿çšããã«ã¯ããŽã«ãŒãã³ãèµ·åããåã« Add
ã¡ãœãããåŒã³åºããŸãããã
sync.Cond
ã«ã€ããŠå¿ããŠããŸã (#72)
èŠçŽ
sync.Cond
ã䜿çšãããšãè€æ°ã®ãŽã«ãŒãã³ã«ç¹°ãè¿ãéç¥ãéä¿¡ã§ããŸãã
errgroup
ã䜿çšããŠããªã (#73)
èŠçŽ
errgroup
ããã±ãŒãžã䜿çšããŠããŽã«ãŒãã³ã®ã°ã«ãŒããåæãããšã©ãŒãš Context ãåŠçã§ããŸãã
sync
åã®ã³ã㌠(#74)
èŠçŽ
sync
åã¯ã³ããŒãããã¹ãã§ã¯ãããŸããã
æšæºã©ã€ãã©ãª
ééã£ãæéãæå®ãã (#75)
èŠçŽ
time.Duration
ãåãå
¥ããé¢æ°ã«ã¯æ³šæãæã£ãŠãã ãããæŽæ°ãæž¡ãããšã¯èš±å¯ãããŠããŸãããæ··ä¹±ãæããªãããã« time API ã䜿çšããããåªããŠãã ããã
æšæºã©ã€ãã©ãªã®å€ãã®é¢æ°ã¯ãint64
åã®ãšã€ãªã¢ã¹ã§ãã time.Duration
ãåãå
¥ããŸãããã ãã1 åäœã® time.Duration
ã¯ãä»ã®ããã°ã©ãã³ã°èšèªã§äžè¬çã«èŠããã 1 ããªç§ã§ã¯ãªãã1 ããç§ãè¡šããŸãããã®çµæãtime.Duration
API ã䜿çšãã代ããã«æ°å€åãæž¡ããšãäºæ³å€ã®åäœãçºçããå¯èœæ§ããããŸãã
ä»èšèªã䜿çšããããšã®ããéçºè
ã®æ¹ã¯ã次ã®ã³ãŒãã«ãã£ãŠ 1 ç§åšæã®æ°ãã time.Ticker
ãçæããããšèãããããããŸããã
ããããªããã1,000 time.Duration
= 1,000 ããç§ã§ãããããæ³å®ãããŠãã 1ç§ ã§ã¯ãªãã1,000 ããç§ = 1 ãã€ã¯ãç§ã®åšæã«ãªããŸãã
æ··ä¹±ãäºæ³å€ã®åäœãæããªãããããã€ã time.Duration
API ã䜿çšããã¹ãã§ãã
ticker = time.NewTicker(time.Microsecond)
// ãããã¯
ticker = time.NewTicker(1000 * time.Nanosecond)
time.After
ãšã¡ã¢ãªãªãŒã¯ (#76)
èŠçŽ
ç¹°ãè¿ãããé¢æ°ïŒã«ãŒãã HTTP ãã³ãã©ãªã©ïŒã§ time.After
ã®åŒã³åºããåé¿ãããšãããŒã¯æã®ã¡ã¢ãªæ¶è²»ãåé¿ã§ããŸããtime.After
ã«ãã£ãŠçæããããªãœãŒã¹ã¯ã timer ãçµäºãããšãã«ã®ã¿è§£æŸãããŸãã
JSON åŠçã§ãããã¡ãªééã (#77)
- åã®åã蟌ã¿ã«ããäºæ³å€ã®åäœ
Go æ§é äœã§åã蟌ã¿ãã£ãŒã«ãã䜿çšããå Žåã¯æ³šæããŠãã ããã ãªããªã json.Marshaler
ã€ã³ã¿ãã§ãŒã¹ãå®è£
ãã time.Time åã蟌ã¿ãã£ãŒã«ãã®ãããªãã£ãããªãã°ãçºçããŠãããã©ã«ãã®ããŒã·ã£ãªã³ã°åäœããªãŒããŒã©ã€ããããå¯èœæ§ãããããã§ãã
- JSON ãš monotonic clock
2 ã€ã® time.Time
æ§é äœãæ¯èŒããå Žåãtime.Time
ã«ã¯ wall clock ãš monotonic clock ã®äž¡æ¹ãå«ãŸããŠããã== æŒç®åã䜿çšããæ¯èŒã¯äž¡æ¹ã® clock ã«å¯ŸããŠè¡ãããããšãæãåºããŠãã ããã
any
ã®ããã
JSON ããŒã¿ã®ã¢ã³ããŒã·ã£ãªã³ã°äžã«ããããæäŸãããšãã«ééããé¿ããããã«ãæ°å€ã¯ããã©ã«ã㧠float64
ã«å€æãããããšã«æ³šæããŠãã ããã
SQL ã§ãããã¡ãªééã (#78)
sql.Open
ãå¿ ãããããŒã¿ããŒã¹ãžã®æ¥ç¶ã確ç«ããããã§ã¯ãªãããšãå¿ããŠãã
èšå®ãè©ŠããããŒã¿ããŒã¹ã«ã¢ã¯ã»ã¹ã§ããããšã確èªããå¿
èŠãããå Žåã¯ã Ping
ãŸã㯠PingContext
ã¡ãœãããåŒã³åºããŸãããã
- ã³ãã¯ã·ã§ã³ããŒãªã³ã°ã®ããšãå¿ãã
å®éçšæ°Žæºã®ã¢ããªã±ãŒã·ã§ã³ã§ã¯ãããŒã¿ããŒã¹æ¥ç¶ãã©ã¡ãŒã¿ãèšå®ããŸãããã
- ããªãã¢ãã¹ããŒãã¡ã³ãã䜿çšããŠããªã
SQL ã®ããªãã¢ãã¹ããŒãã¡ã³ãã䜿çšãããšãã¯ãšãªãããå¹ççãã€ç¢ºå®ã«ãªããŸãã
- null å€ã誀ã£ãæ¹æ³ã§åŠçããŠãã
ããŒãã«å
ã® null ã蚱容ãããŠããåã¯ããã€ã³ã¿ãŸã㯠sql.NullXXX
åã䜿çšããŠåŠçããŸãããã
- è¡ã®å埩åŠçã«ãããšã©ãŒãåŠçããªã
è¡ã®å埩åŠçã®åŸã« sql.Rows
ã® Err
ã¡ãœãããåŒã³åºããŠã次ã®è¡ã®æºåäžã«ãšã©ãŒãèŠéããŠããªãããšã確èªããŸãããã
äžæçãªãªãœãŒã¹ïŒ HTTP bodyãsql.Rows
ãããã³ os.File
ïŒãéããŠããªã (#79)
èŠçŽ
ãªãŒã¯ãé¿ããããã«ã io.Closer
ãå®è£
ããŠãããã¹ãŠã®æ§é äœãæåŸã«ã¯éããŸãããã
HTTP ãªã¯ãšã¹ãã«å¿çããåŸã® return æãå¿ããŠããŸã (#80)
èŠçŽ
HTTP ãã³ãã©ã®å®è£
ã§ã®äºæ³å€ã®åäœãé¿ãããããhttp.Error
ã®åŸã«ãã³ãã©ãåæ¢ãããå Žåã¯ãreturn
æãå¿ããªãããã«ããŠãã ããã
æšæºã® HTTP ã¯ã©ã€ã¢ã³ããšãµãŒããŒã䜿çšããŠãã (#81)
èŠçŽ
å®éçšæ°Žæºã®ã¢ããªã±ãŒã·ã§ã³ãæ±ããŠããå Žåã¯ãæšæºã® HTTP ã¯ã©ã€ã¢ã³ããšãµãŒããŒã®å®è£ ã䜿çšããªãã§ãã ããããããã®å®è£ ã«ã¯ãã¿ã€ã ã¢ãŠãã皌åç°å¢ã§å¿ é ã§ããã¹ãåäœãæ¬ èœããŠããŸãã
ãã¹ã
ãã¹ããåé¡ããŠããªãïŒãã«ãã¿ã°ãç°å¢å€æ°ãã·ã§ãŒãã¢ãŒãïŒ (#82)
èŠçŽ
ãã«ããã©ã°ãç°å¢å€æ°ããŸãã¯ã·ã§ãŒãã¢ãŒãã䜿çšããŠãã¹ããåé¡ãããšããã¹ãããã»ã¹ãããå¹ççã«ãªããŸãããã«ããã©ã°ãŸãã¯ç°å¢å€æ°ã䜿çšããŠãã¹ãã«ããŽãªïŒããšãã°ãåäœãã¹ããšçµ±åãã¹ãïŒãäœæããçæéã®ãã¹ããšé·æéã®ãã¹ããåºå¥ããããšã§ãå®è¡ãããã¹ãã®çš®é¡ã決å®ã§ããŸãã
-race
ãã©ã°ãæå¹ã«ããŠããªã (#83)
èŠçŽ
䞊è¡ã¢ããªã±ãŒã·ã§ã³ãäœæããå Žåã¯ã -race
ãã©ã°ãæå¹ã«ããããšã匷ããå§ãããŸããããããããšã§ããœãããŠã§ã¢ã®ãã°ã«ã€ãªããå¯èœæ§ã®ããæœåšçãªããŒã¿ç«¶åãçºèŠã§ããããã«ãªããŸãã
ãã¹ãå®è¡ã¢ãŒãïŒ -parallel
ããã³ -shuffle
ïŒã䜿çšããŠããªã (#84)
èŠçŽ
-parallel
ãã©ã°ã䜿çšããã®ã¯ãç¹ã«é·æéå®è¡ããããã¹ããé«éåããã®ã«å¹æçã§ãã -shuffle
ãã©ã°ã䜿çšãããšããã¹ãã¹ã€ãŒãããã°ãé ãå¯èœæ§ã®ããééã£ãä»®å®ã«äŸåããªãããã«ããããšãã§ããŸãã
ããŒãã«é§åãã¹ãã䜿çšããªã (#85)
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