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

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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
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patterns/interfaces.md
+30 -28
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@@ -6,22 +6,22 @@ Patterns extracted from the Go standard library source code.
## 1. Small Interfaces (1-2 Methods)
### Source: `src/io/io.go:80-92` (Reader), `93-103` (Writer), `105-109` (Closer)
### Source: [src/io/io.go#L80](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L80) (Reader), `93-103` (Writer), `105-109` (Closer)
Go's most powerful interfaces have exactly **one method**:
```go
// src/io/io.go:80-92
// [src/io/io.go#L80](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L80)
type Reader interface {
Read(p []byte) (n int, err error)
}
// src/io/io.go:93-103
// [src/io/io.go#L93](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L93)
type Writer interface {
Write(p []byte) (n int, err error)
}
// src/io/io.go:105-109
// [src/io/io.go#L105](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L105)
type Closer interface {
Close() error
}
@@ -120,30 +120,30 @@ Large interfaces are hard to implement, hard to mock, and couple consumers to ca
## 2. Interface Composition
### Source: `src/io/io.go:131-155`
### Source: [src/io/io.go#L131](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L131)
Compose small interfaces into larger ones only when needed:
```go
// src/io/io.go:131-134
// [src/io/io.go#L131](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L131)
type ReadWriter interface {
Reader
Writer
}
// src/io/io.go:136-139
// [src/io/io.go#L136](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L136)
type ReadCloser interface {
Reader
Closer
}
// src/io/io.go:141-144
// [src/io/io.go#L141](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L141)
type WriteCloser interface {
Writer
Closer
}
// src/io/io.go:146-150
// [src/io/io.go#L146](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L146)
type ReadWriteCloser interface {
Reader
Writer
@@ -168,13 +168,13 @@ func processData(rw ReadWriteCloser) {
## 3. Accept Interfaces, Return Structs
### Source: `src/io/io.go:461` (LimitReader), `src/io/io.go:618` (TeeReader)
### Source: [src/io/io.go#L461](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L461) (LimitReader), [src/io/io.go#L618](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L618) (TeeReader)
```go
// src/io/io.go:461
func LimitReader(r Reader, n int64) Reader { return &LimitedReader{r, n} }
// src/io/io.go:467-471
// [src/io/io.go#L467](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L467)
type LimitedReader struct {
R Reader // underlying reader
N int64 // max bytes remaining
@@ -182,7 +182,7 @@ type LimitedReader struct {
```
```go
// src/io/io.go:618-620
// [src/io/io.go#L618](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L618)
func TeeReader(r Reader, w Writer) Reader {
return &teeReader{r, w}
}
@@ -272,7 +272,7 @@ func NewServer() ServerInterface // hides useful config fields
## 4. Interface Satisfaction as a Compile-Time Check
### Source: `src/io/io.go:645`, `src/net/http/server.go:4071`
### Source: [src/io/io.go#L645](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L645), [src/net/http/server.go#L4071](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L4071)
```go
// src/io/io.go:645
@@ -299,10 +299,10 @@ func doSomething(w ResponseWriter) {
## 5. Interface-Based Polymorphism (sort.Interface)
### Source: `src/sort/sort.go:16-41`
### Source: [src/sort/sort.go#L16](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sort/sort.go#L16)
```go
// src/sort/sort.go:16-41
// [src/sort/sort.go#L16](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/sort/sort.go#L16)
type Interface interface {
Len() int
Less(i, j int) bool
@@ -328,17 +328,17 @@ Note: Since Go 1.21, `slices.SortFunc` is preferred for slices (generic + faster
## 6. The Adapter Pattern (HandlerFunc)
### Source: `src/net/http/server.go:2334-2342`
### Source: [src/net/http/server.go#L2334](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L2334)
```go
// src/net/http/server.go:2334-2338
// [src/net/http/server.go#L2334](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L2334)
// The HandlerFunc type is an adapter to allow the use of
// ordinary functions as HTTP handlers. If f is a function
// with the appropriate signature, HandlerFunc(f) is a
// Handler that calls f.
type HandlerFunc func(ResponseWriter, *Request)
// src/net/http/server.go:2341-2342
// [src/net/http/server.go#L2341](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L2341)
// ServeHTTP calls f(w, r).
func (f HandlerFunc) ServeHTTP(w ResponseWriter, r *Request) {
f(w, r)
@@ -436,15 +436,15 @@ func (h myHandler) ServeHTTP(w ResponseWriter, r *Request) {
## 7. Optional Interfaces (Runtime Feature Detection)
### Source: `src/net/http/server.go:165-175` (Flusher), `src/net/http/server.go:183-206` (Hijacker)
### Source: [src/net/http/server.go#L165](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L165) (Flusher), [src/net/http/server.go#L183](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L183) (Hijacker)
```go
// src/net/http/server.go:165-170
// [src/net/http/server.go#L165](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L165)
type Flusher interface {
Flush()
}
// src/net/http/server.go:183-206
// [src/net/http/server.go#L183](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/net/http/server.go#L183)
type Hijacker interface {
Hijack() (net.Conn, *bufio.ReadWriter, error)
}
@@ -564,10 +564,10 @@ type ResponseWriter interface {
## 8. The Stringer Interface (Convention-Based Behavior)
### Source: `src/fmt/print.go:63-66`
### Source: [src/fmt/print.go#L63](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/fmt/print.go#L63)
```go
// src/fmt/print.go:63-66
// [src/fmt/print.go#L63](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/fmt/print.go#L63)
type Stringer interface {
String() string
}
@@ -596,10 +596,10 @@ func printThing(v any) string {
## 9. Interface Upgrade Pattern (WriterTo/ReaderFrom in io.Copy)
### Source: `src/io/io.go:410-417`
### Source: [src/io/io.go#L410](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L410)
```go
// src/io/io.go:410-417
// [src/io/io.go#L410](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/io/io.go#L410)
func copyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
// If the reader has a WriteTo method, use it to do the copy.
// Avoids an allocation and a copy.
@@ -632,15 +632,15 @@ func Copy(dst Writer, src Reader) {
## 10. The driver.Driver Pattern (Plugin Interfaces)
### Source: `src/database/sql/driver/driver.go:85-97`, `104-112`
### Source: [src/database/sql/driver/driver.go#L85](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/database/sql/driver/driver.go#L85), `104-112`
```go
// src/database/sql/driver/driver.go:85-97
// [src/database/sql/driver/driver.go#L85](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/database/sql/driver/driver.go#L85)
type Driver interface {
Open(name string) (Conn, error)
}
// src/database/sql/driver/driver.go:104-112
// [src/database/sql/driver/driver.go#L104](https://github.com/golang/go/blob/17bd5ab8c650155dd2bd09f7005726552639eea0/src/database/sql/driver/driver.go#L104)
type DriverContext interface {
OpenConnector(name string) (Connector, error)
}
@@ -676,3 +676,5 @@ type Driver interface {
| Compile-time interface checks | `var _ Interface = (*Type)(nil)` |
| Runtime interface upgrade for optimization | `io.Copy` → `WriterTo`/`ReaderFrom` |
| Plugin/driver interfaces start minimal | `database/sql/driver.Driver` |
<!-- PATTERN_COMPLETE -->