What can you do with bytes?

Bits.js

// notes: http://jsperf.com/transloc-getters
// http://www.bytearray.org/?p=711
// testing in Nodejs console

function Bits() {
    this._buffer = 0;
    this._length = 0;

    // 写入时虚拟指针
    this._wpointer = 0;
    // 读出时虚拟指针
    this._rpointer = 0;
}

Bits.prototype = {
    write: function(bit) {
        if ( 1 < bit || 0 > bit ) {
            throw new Error('只能输入0或者1.');
        }
        // 从右开始写入
        return this._buffer |= (bit << (this._length = this._wpointer++));
    },
    read: function() {
        if (this._rpointer > this._length) {
            throw new Error('目标读取位置超出元组的长度')
        }
        //return this._buffer & (1 << this._rpointer++);
        // 从右开始读出
        return +((this._buffer & (1 << this._rpointer++)) >> (this._rpointer - 1) != 0);
    },
    get buffer() {
        return this._buffer;
    },
    get rpointer() {
        return this._rpointer;
    },
    get wpointer() {
        return this._wpointer;
    },
    set rpointer(r) {
        this._rpointer = r;
    },
    set wpointer(w) {
        this._wpointer = w;
    }
};

var b = new Bits();
console.log(b.write(1).toString(2));
console.log(b.write(0).toString(2));
console.log(b.write(1).toString(2));
console.log(b.write(1).toString(2));

console.log(b.read());
console.log(b.read());
b.rpointer = 2;
console.log(b.read());
console.log(b.read())

console.log(b.rpointer);
console.log(b.wpointer);
console.log(b.buffer);