go-ethereum/rlp/iterator.go

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// Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package rlp
type listIterator struct {
data []byte
next []byte
err error
}
// NewListIterator creates an iterator for the (list) represented by data
func NewListIterator(data RawValue) (*listIterator, error) {
k, t, c, err := readKind(data)
if err != nil {
return nil, err
}
if k != List {
return nil, ErrExpectedList
}
it := &listIterator{
data: data[t : t+c],
}
return it, nil
}
// Next forwards the iterator one step, returns true if it was not at end yet
func (it *listIterator) Next() bool {
if len(it.data) == 0 {
return false
}
_, t, c, err := readKind(it.data)
it.next = it.data[:t+c]
it.data = it.data[t+c:]
it.err = err
return true
}
// Value returns the current value
func (it *listIterator) Value() []byte {
return it.next
}
func (it *listIterator) Err() error {
return it.err
}