55 lines
1.6 KiB
Go
55 lines
1.6 KiB
Go
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// Copyright 2014 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package rlp
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import (
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"fmt"
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"io"
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)
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type MyCoolType struct {
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Name string
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a, b uint
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}
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// EncodeRLP writes x as RLP list [a, b] that omits the Name field.
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func (x *MyCoolType) EncodeRLP(w io.Writer) (err error) {
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// Note: the receiver can be a nil pointer. This allows you to
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// control the encoding of nil, but it also means that you have to
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// check for a nil receiver.
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if x == nil {
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err = Encode(w, []uint{0, 0})
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} else {
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err = Encode(w, []uint{x.a, x.b})
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}
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return err
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}
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func ExampleEncoder() {
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var t *MyCoolType // t is nil pointer to MyCoolType
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bytes, _ := EncodeToBytes(t)
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fmt.Printf("%v → %X\n", t, bytes)
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t = &MyCoolType{Name: "foobar", a: 5, b: 6}
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bytes, _ = EncodeToBytes(t)
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fmt.Printf("%v → %X\n", t, bytes)
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// Output:
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// <nil> → C28080
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// &{foobar 5 6} → C20506
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}
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