encoder_example_test.go 1.4 KB

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  1. // Copyright 2014 The go-ethereum Authors
  2. // This file is part of the go-ethereum library.
  3. //
  4. // The go-ethereum library is free software: you can redistribute it and/or modify
  5. // it under the terms of the GNU Lesser General Public License as published by
  6. // the Free Software Foundation, either version 3 of the License, or
  7. // (at your option) any later version.
  8. //
  9. // The go-ethereum library is distributed in the hope that it will be useful,
  10. // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11. // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12. // GNU Lesser General Public License for more details.
  13. //
  14. // You should have received a copy of the GNU Lesser General Public License
  15. // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
  16. package rlp_test
  17. import (
  18. "fmt"
  19. "io"
  20. "github.com/ethereum/go-ethereum/rlp"
  21. )
  22. type MyCoolType struct {
  23. Name string
  24. a, b uint
  25. }
  26. // EncodeRLP writes x as RLP list [a, b] that omits the Name field.
  27. func (x *MyCoolType) EncodeRLP(w io.Writer) (err error) {
  28. return rlp.Encode(w, []uint{x.a, x.b})
  29. }
  30. func ExampleEncoder() {
  31. var t *MyCoolType // t is nil pointer to MyCoolType
  32. bytes, _ := rlp.EncodeToBytes(t)
  33. fmt.Printf("%v → %X\n", t, bytes)
  34. t = &MyCoolType{Name: "foobar", a: 5, b: 6}
  35. bytes, _ = rlp.EncodeToBytes(t)
  36. fmt.Printf("%v → %X\n", t, bytes)
  37. // Output:
  38. // <nil> → C0
  39. // &{foobar 5 6} → C20506
  40. }