docs: function filter(unparsed) {
    var cmds = this.commands()
      , alias = this.finder.getCommandByName;
    var i, l = unparsed.length;
    for(i = 0;i < l;i++) {
      //console.log('unparsed filter %s', unparsed[i]);
      if(alias(unparsed[i], cmds)) {
        unparsed.splice(i, 1);
        i--;
        l--;
      }
    }
    //console.log('return %j', unparsed);
    return unparsed;
  }