How to use

first

function

in

CollectionChain

_.chain(os.networkInterfaces())
  .values()
  .flatten()
  .filter(function(val) {
   return (val.family == 'IPv4' && val.internal == false)
  })
  .map('address')
  .first()
  .value()

/**
 * extract broadcast addr
 * @param  {string} line
 * @return {string,null}      xxx.xxx.xxx.xxx
 */
function getBroadcastAddr(line) {
 if (!_.includes(line, BCAST)) {
  return null;
 }

 // inet adr:1.1.1.77  Bcast:1.1.1.255  Masque:1.1.1.0
 // @todo oh boy. this is ugly.
 return _.chain(line)
  .split(BCAST)
  .slice(1)
  .first()
  .value()
  .substring(1)
  .split(' ')[0];
}