helmsman.js
function isOneOrMore(commands, iterator) {
    var list = commands.filter(iterator);

    if (list.length === 1) {
      return list[0];
    } else if (list.length > 1) {
      return new Error(util.format('There are %d options for "%s": %s',
        list.length, cmd, list.join(', ')));
    }

    return false;
  }
function isOneOrMore(commands, iterator) {
    var list = commands.filter(iterator);

    if (list.length === 1) {
      return list[0];
    } else if (list.length > 1) {
      return new Error(util.format('There are %d options for "%s": %s',
        list.length, cmd, list.join(', ')));
    }

    return false;
  }
function isOneOrMore ( commands , iterator ) { var list = commands . filter ( iterator ) ; if ( list . length === 1 ) { return list [ 0 ] ; } else if ( list . length > 1 ) { return new Error ( util . format ( 'There are %d options for "%s": %s' , list . length , cmd , list . join ( ', ' ) ) ) ; } return false ; }
Determine how many commands match the iterator. Return one if command,
Determine how many commands match the iterator . Return one if command