/**
  *
  * @param array $backtrace
  * @return TokenStream
  */
 public function parseBacktrace(array $backtrace, VarParser $varParser)
 {
     $builder = new TokenStreamBuilder();
     $i = 0;
     foreach ($backtrace as $stackFrame) {
         $builder->addPlainText('#' . ++$i)->addWhitespece()->addStream($this->parseStackFrame($stackFrame, $varParser))->addNewLine();
     }
     return $builder->getStream();
 }