87 lines
1.6 KiB
Go
87 lines
1.6 KiB
Go
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package main
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import "fmt"
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import "io"
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import "log"
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import "reflect"
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import "strings"
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import "encoding/json"
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type S struct{
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blah int
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foo string
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}
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func (s *S) addr() { fmt.Printf("%p\n", s) }
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type Codec interface {
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Encode(w io.Writer, v interface{}) error
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Decode(r io.Reader, v interface{}) error
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}
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func (jsonCodec) Encode(w io.Writer, v interface{}) error {
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return json.NewEncoder(w).Encode(v)
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}
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func (jsonCodec) Decode(r io.Reader, v interface{}) error {
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return json.NewDecoder(r).Decode(v)
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}
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var JSON Codec = jsonCodec{}
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type jsonCodec struct{}
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type buttons interface {
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Encode(w io.Writer, v interface{}) error
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Decode(r io.Reader, v interface{}) error
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}
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type foo struct{}
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type goo struct{
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test int
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}
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func bar(baz interface{}) {
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log.Println("baz =", baz)
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log.Println("reflect.TypeOf(baz) =", reflect.TypeOf(baz))
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switch f := baz.(type) {
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case int:
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log.Println("baz.(type) is an int =", f * 3)
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case *foo: // f is of type *foo
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log.Println("baz.(type) is known as *foo")
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default: // f is some other type
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log.Println("baz.(type) =", f)
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}
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}
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func main() {
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var a, b S
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a.addr() // 0x1beeb0
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b.addr() // 0x1beeb0
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f := &foo{}
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bar(f) // every type implements interface{}. Nothing special required
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g := &goo{}
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g.test = 4
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bar(g) // every type implements interface{}. Nothing special required
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bar("hello") // every type implements interface{}. Nothing special required
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// what is this?
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// s := &Service{
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// Codec: JSON,
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// }
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r := strings.NewReader("Hello, Reader!")
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err := JSON.Decode(r, "afjd")
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log.Println("JSON.Decoder err =", err)
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// err := JSON.Encode(w, obj)
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// log.Println("err =", err)
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}
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