// +build ignore,OMIT package main import ( "encoding/binary" "io" "log" "os" ) type Gopher struct { Name string AgeYears int } type binWriter struct { w io.Writer size int64 err error } // Write writes a value to the provided writer in little endian form. func (w *binWriter) Write(v interface{}) { if w.err != nil { return } switch x := v.(type) { // HL case string: w.Write(int32(len(x))) w.Write([]byte(x)) case int: w.Write(int64(x)) default: if w.err = binary.Write(w.w, binary.LittleEndian, v); w.err == nil { w.size += int64(binary.Size(v)) } } } func (g *Gopher) WriteTo(w io.Writer) (int64, error) { bw := &binWriter{w: w} bw.Write(g.Name) bw.Write(g.AgeYears) return bw.size, bw.err } func main() { g := &Gopher{ Name: "Gophertiti", AgeYears: 3382, } if _, err := g.WriteTo(os.Stdout); err != nil { log.Printf("DumpBinary: %v\n", err) } }