// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package utf8 implements functions and constants to support text encoded in
// UTF-8. It includes functions to translate between runes and UTF-8 byte sequences.
// See https://en.wikipedia.org/wiki/UTF-8
package utf8

type RuneIter struct {
    src  []byte
    pos  int32
    start int32
    r    rune
    size int32
}

func Iter(s []byte) RuneIter { return RuneIter{src: s} }

func (it *RuneIter) Next() bool {
    if it.pos >= int32(len(it.src)) { return false }
    it.start = it.pos
    r, sz := DecodeRune(it.src[it.pos:])
    it.r = r
    it.size = int32(sz)
    return true
}

func (it *RuneIter) Rune() rune { return it.r }

func (it *RuneIter) Advance() { it.pos += it.size }

func (it *RuneIter) Pos() int32 { return it.start }

func (it *RuneIter) Size() int32 { return it.size }