lib/address.js
function privKeyToWIF(privKey) {
  var toCompressed = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : false;
  var wif = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : zconfig.mainnet.wif;

  if (toCompressed) privKey = privKey + '01';

  return bs58check.encode(Buffer.from(wif + privKey, 'hex'));
}
function privKeyToWIF(privKey) {
  var toCompressed = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : false;
  var wif = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : zconfig.mainnet.wif;

  if (toCompressed) privKey = privKey + '01';

  return bs58check.encode(Buffer.from(wif + privKey, 'hex'));
}
/*
Converts a private key to WIF format
@param {String} privKey (private key)
@param {boolean} toCompressed (Convert to WIF compressed key or nah)
@param {String} wif (wif hashing bytes (default: 0x80))
@return {Sting} WIF format (uncompressed)