original_string: public function isFile($filename)
      {
          $absolutePath = $this->parser->absoluteFilePath($filename);
  
          return file_exists($absolutePath) && is_file($absolutePath) ? $absolutePath : null;
      }
code: public function isFile($filename)
      {
          $absolutePath = $this->parser->absoluteFilePath($filename);
  
          return file_exists($absolutePath) && is_file($absolutePath) ? $absolutePath : null;
      }
code_tokens: public function isFile ( $ filename ) { $ absolutePath = $ this -> parser -> absoluteFilePath ( $ filename ) ; return file_exists ( $ absolutePath ) && is_file ( $ absolutePath ) ? $ absolutePath : null ; }
docstring: Is this filename any type of file?
  
  @param  string  $filename
  @return boolean
docstring_tokens: Is this filename any type of file?