original_string: public function getDescriptionUrl($revision = null)
  	{
  		// Without revision, use current info
  		if (!isset($revision)) {
  			return $this->info['descriptionurl'];
  		}
  
  		// Obtain the properties of the revision
  		if (($info = $this->getRevision($revision)) === null) {
  			return null;
  		}
  
  		return $info['descriptionurl'];
  	}
code: public function getDescriptionUrl($revision = null)
  	{
  		// Without revision, use current info
  		if (!isset($revision)) {
  			return $this->info['descriptionurl'];
  		}
  
  		// Obtain the properties of the revision
  		if (($info = $this->getRevision($revision)) === null) {
  			return null;
  		}
  
  		return $info['descriptionurl'];
  	}
code_tokens: public function getDescriptionUrl ( $ revision = null ) { // Without revision, use current info if ( ! isset ( $ revision ) ) { return $ this -> info [ 'descriptionurl' ] ; } // Obtain the properties of the revision if ( ( $ info = $ this -> getRevision ( $ revision ) ) === null ) { return null ; } return $ info [ 'descriptionurl' ] ; }
docstring: Returns the description URL of this file,
  or of its specified revision.
  
  @param   mixed  $revision  The index or timestamp of the revision (optional)
  @return  mixed             The description URL of this file (string),
  or null if revision not found
docstring_tokens: Returns the description URL of this file or of its specified revision .