original_string: protected function _getRealOffset($offset)
      {
          /* Optimize: check for base $offset in array first. */
          if (parent::offsetExists($offset)) {
              return $offset;
          }
  
          foreach (array_keys($this->getArrayCopy()) as $key) {
              if (strcasecmp($key, $offset) === 0) {
                  return $key;
              }
          }
  
          return null;
      }
code: protected function _getRealOffset($offset)
      {
          /* Optimize: check for base $offset in array first. */
          if (parent::offsetExists($offset)) {
              return $offset;
          }
  
          foreach (array_keys($this->getArrayCopy()) as $key) {
              if (strcasecmp($key, $offset) === 0) {
                  return $key;
              }
          }
  
          return null;
      }
code_tokens: protected function _getRealOffset ( $ offset ) { /* Optimize: check for base $offset in array first. */ if ( parent :: offsetExists ( $ offset ) ) { return $ offset ; } foreach ( array_keys ( $ this -> getArrayCopy ( ) ) as $ key ) { if ( strcasecmp ( $ key , $ offset ) === 0 ) { return $ key ; } } return null ; }
docstring: Determines the actual array offset given the input offset.
  
  @param string $offset  Input offset.
  
  @return string  Real offset or null.
docstring_tokens: Determines the actual array offset given the input offset .