lib/docs/retriever.js
function getDefaultArgs() {
  var results = [];
  DEFAULT_PATHS.forEach(function(dir) {
    if( fs.existsSync(dir) ) results.push(dir);
  });
  return results.length == 0 ? null : results;
}
function getDefaultArgs() {
  var results = [];
  DEFAULT_PATHS.forEach(function(dir) {
    if( fs.existsSync(dir) ) results.push(dir);
  });
  return results.length == 0 ? null : results;
}
Returns an Array of default paths.