var utf8ArrayToStr = (function () {
  var charCache = new Array(128)  // Preallocate the cache for the common single byte chars
  var charFromCodePt = String.fromCodePoint || String.fromCharCode
  var result:any = []

  return function (array:any) {
    var codePt, byte1
    var buffLen = array.length

    result.length = 0

    for (var i = 0; i < buffLen;) {
      byte1 = array[i++]

      if (byte1 <= 0x7F) {
        codePt = byte1
      } else if (byte1 <= 0xDF) {
        codePt = ((byte1 & 0x1F) << 6) | (array[i++] & 0x3F)
      } else if (byte1 <= 0xEF) {
        codePt = ((byte1 & 0x0F) << 12) | ((array[i++] & 0x3F) << 6) | (array[i++] & 0x3F)
      } else if (String.fromCodePoint()) {
        codePt = ((byte1 & 0x07) << 18) | ((array[i++] & 0x3F) << 12) | ((array[i++] & 0x3F) << 6) | (array[i++] & 0x3F)
      } else {
        codePt = 63    // Cannot convertLongFields four byte code points, so use "?" instead
        i += 3
      }

      result.push(charCache[codePt] || (charCache[codePt] = charFromCodePt(codePt)))
    }

    return result.join('')
  }
})

export const Utf8ArrayToStr = utf8ArrayToStr()