Base16 array to hex

Base16.js

function Uint8Array2hex(arr) {
    var hexEncodeArray = '0123456789abcdef'.split('');
    var s = '';
    for (var i = 0; i < arr.length; i++) {
        var code = arr[i];
        s += hexEncodeArray[code >>> 4];
        s += hexEncodeArray[code & 0x0F];
    }
    return s;
}

// alternative 1

  function bytesToHex(p) {
    /** @const */
    var enc = '0123456789abcdef'.split('');

    var len = p.length,
        arr = [],
        i = 0;

    for (; i < len; i++) {
        arr.push(enc[(p[i]>>>4) & 15]);
        arr.push(enc[(p[i]>>>0) & 15]);
    }
    return arr.join('');
  }
  
// alternative 2

var hex = {
    decode: function(text) {
        return text.match(/.{2}/g).map(function(byte) {
            return parseInt(byte, 16);
        });
    },
    encode: function(bytes) {
        var result = [];
        for (var i = 0, hex; i < bytes.length; i++) {
            hex = bytes[i].toString(16);
            if (hex.length < 2) {
                hex = '0' + hex;
            }
            result.push(hex);
        }
        return result.join('');
    }
};