rodin/go-patterns
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

feat: add source hyperlinks (commit SHA permalinks) to all pattern files

Browse Source 
Every source reference now links to the exact line in the golang/go
repo at commit 17bd5ab. Added PATTERN_COMPLETE sentinels.

Total: 154 hyperlinks across 10 topic files.
This commit is contained in:
Rodin
2026-04-30 14:42:20 -07:00
parent 99c0865e93
commit c8ed244a07
9 changed files with 172 additions and 144 deletions
Download Patch File Download Diff File Expand all files Collapse all files
patterns/concurrency.md
+31 -29
View File
@@ -6,10 +6,10 @@ Patterns extracted from the Go standard library source code.
## 1. sync.Mutex — The Basic Lock
### Source: `src/sync/mutex.go:18-34`, `src/sync/mutex.go:42-67`
### Source: [src/sync/mutex.go#L18](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/mutex.go#L18), [src/sync/mutex.go#L42](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/mutex.go#L42)
```go
// src/sync/mutex.go:18-34
// [src/sync/mutex.go#L18](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/mutex.go#L18)
// A Mutex is a mutual exclusion lock.
// The zero value for a Mutex is an unlocked mutex.
//
@@ -19,13 +19,13 @@ type Mutex struct {
mu isync.Mutex
}
// src/sync/mutex.go:36-39
// [src/sync/mutex.go#L36](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/mutex.go#L36)
type Locker interface {
Lock()
Unlock()
}
// src/sync/mutex.go:43-46
// [src/sync/mutex.go#L43](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/mutex.go#L43)
func (m *Mutex) Lock() {
m.mu.Lock()
}
@@ -146,24 +146,24 @@ mu.Unlock()
## 2. sync.Once — Exactly-Once Initialization
### Source: `src/sync/once.go:12-36`, `src/sync/once.go:56-79`
### Source: [src/sync/once.go#L12](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/once.go#L12), [src/sync/once.go#L56](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/once.go#L56)
```go
// src/sync/once.go:12-23
// [src/sync/once.go#L12](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/once.go#L12)
type Once struct {
_ noCopy
done atomic.Bool
m Mutex
}
// src/sync/once.go:56-63
// [src/sync/once.go#L56](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/once.go#L56)
func (o *Once) Do(f func()) {
if !o.done.Load() {
o.doSlow(f)
}
}
// src/sync/once.go:65-72
// [src/sync/once.go#L65](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/once.go#L65)
func (o *Once) doSlow(f func()) {
o.m.Lock()
defer o.m.Unlock()
@@ -301,10 +301,10 @@ once.Do(func() {
## 3. sync.WaitGroup — Waiting for Goroutine Completion
### Source: `src/sync/waitgroup.go:14-43`, `src/sync/waitgroup.go:236-260`
### Source: [src/sync/waitgroup.go#L14](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/waitgroup.go#L14), [src/sync/waitgroup.go#L236](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/waitgroup.go#L236)
```go
// src/sync/waitgroup.go:14-43
// [src/sync/waitgroup.go#L14](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/waitgroup.go#L14)
// Typically, a main goroutine will start tasks by calling WaitGroup.Go
// and then wait for all tasks to complete by calling WaitGroup.Wait:
//
@@ -322,7 +322,7 @@ type WaitGroup struct {
### Go 1.25+: WaitGroup.Go
```go
// src/sync/waitgroup.go:236-260
// [src/sync/waitgroup.go#L236](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/waitgroup.go#L236)
func (wg *WaitGroup) Go(f func()) {
wg.Add(1)
go func() {
@@ -374,10 +374,10 @@ wg.Wait()
## 4. sync.Pool — Object Reuse for GC Pressure
### Source: `src/sync/pool.go:44-63`
### Source: [src/sync/pool.go#L44](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/pool.go#L44)
```go
// src/sync/pool.go:44-63
// [src/sync/pool.go#L44](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/pool.go#L44)
// Pool's purpose is to cache allocated but unused items for later reuse,
// relieving pressure on the garbage collector. That is, it makes it easy to
// build efficient, thread-safe free lists.
@@ -439,15 +439,15 @@ pool.Put(buf) // still has data from last use
## 5. Channel as Done Signal (Context Pattern)
### Source: `src/context/context.go:83-100` (Done channel), `src/io/pipe.go:42-45`
### Source: [src/context/context.go#L83](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/context/context.go#L83) (Done channel), [src/io/pipe.go#L42](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L42)
```go
// src/context/context.go:83-100
// [src/context/context.go#L83](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/context/context.go#L83)
// Done returns a channel that's closed when work done on behalf of this
// context should be canceled.
Done() <-chan struct{}
// src/io/pipe.go:42-45
// [src/io/pipe.go#L42](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L42)
type pipe struct {
once sync.Once
done chan struct{} // closed on pipe close
@@ -583,10 +583,10 @@ close(done)
## 6. Context Propagation Rules
### Source: `src/context/context.go:37-48`
### Source: [src/context/context.go#L37](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/context/context.go#L37)
```go
// src/context/context.go:37-48
// [src/context/context.go#L37](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/context/context.go#L37)
// Do not store Contexts inside a struct type; instead, pass a Context
// explicitly to each function that needs it. The Context should be the first
// parameter, typically named ctx:
@@ -622,10 +622,10 @@ func doWork(data Data, ctx context.Context) // wrong position
## 7. Context Cancellation with Timeout
### Source: `src/net/http/server.go:4007-4050` (TimeoutHandler)
### Source: [src/net/http/server.go#L4007](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L4007) (TimeoutHandler)
```go
// src/net/http/server.go:4011-4050
// [src/net/http/server.go#L4011](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L4011)
func (h *timeoutHandler) ServeHTTP(w ResponseWriter, r *Request) {
ctx, cancelCtx := context.WithTimeout(r.Context(), h.dt)
defer cancelCtx()
@@ -675,10 +675,10 @@ func longWork(ctx context.Context) {
## 8. Select with Non-Blocking Check
### Source: `src/io/pipe.go:51-60`
### Source: [src/io/pipe.go#L51](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L51)
```go
// src/io/pipe.go:51-60
// [src/io/pipe.go#L51](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L51)
func (p *pipe) read(b []byte) (n int, err error) {
select {
case <-p.done:
@@ -719,17 +719,17 @@ for {
## 9. Channel Pipeline (io.Pipe)
### Source: `src/io/pipe.go:38-45`, `src/io/pipe.go:195-205`
### Source: [src/io/pipe.go#L38](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L38), [src/io/pipe.go#L195](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L195)
```go
// src/io/pipe.go:38-45
// [src/io/pipe.go#L38](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L38)
type pipe struct {
wrCh chan []byte // writer sends data slices
rdCh chan int // reader returns bytes consumed
done chan struct{}
}
// src/io/pipe.go:195-205
// [src/io/pipe.go#L195](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/pipe.go#L195)
func Pipe() (*PipeReader, *PipeWriter) {
pw := &PipeWriter{r: PipeReader{pipe: pipe{
wrCh: make(chan []byte), // unbuffered
@@ -868,10 +868,10 @@ func produce() <-chan int {
## 10. Background Worker with Context Shutdown
### Source: `src/database/sql/sql.go:836-843`
### Source: [src/database/sql/sql.go#L836](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/database/sql/sql.go#L836)
```go
// src/database/sql/sql.go:836-843
// [src/database/sql/sql.go#L836](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/database/sql/sql.go#L836)
func OpenDB(c driver.Connector) *DB {
ctx, cancel := context.WithCancel(context.Background())
db := &DB{
@@ -903,10 +903,10 @@ go func() {
## 11. noCopy — Preventing Value Copies
### Source: `src/sync/cond.go:120-126`
### Source: [src/sync/cond.go#L120](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/cond.go#L120)
```go
// src/sync/cond.go:120-126
// [src/sync/cond.go#L120](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sync/cond.go#L120)
type noCopy struct{}
// Lock is a no-op used by -copylocks checker from `go vet`.
@@ -947,3 +947,5 @@ func doWork(wg *sync.WaitGroup) {
| Backpressure between producer/consumer | Unbuffered channels |
| Long-lived background worker | Goroutine + context cancellation |
| Prevent struct copying | Embed `noCopy` field |
<!-- PATTERN_COMPLETE -->