original_string: public function header($name)
      {
          deprecationWarning(
              'ServerRequest::header() is deprecated. ' .
              'The automatic fallback to env() will be removed in 4.0.0, see getHeader()'
          );
  
          $name = $this->normalizeHeaderName($name);
  
          return $this->getEnv($name);
      }
code: public function header($name)
      {
          deprecationWarning(
              'ServerRequest::header() is deprecated. ' .
              'The automatic fallback to env() will be removed in 4.0.0, see getHeader()'
          );
  
          $name = $this->normalizeHeaderName($name);
  
          return $this->getEnv($name);
      }
code_tokens: public function header ( $ name ) { deprecationWarning ( 'ServerRequest::header() is deprecated. ' . 'The automatic fallback to env() will be removed in 4.0.0, see getHeader()' ) ; $ name = $ this -> normalizeHeaderName ( $ name ) ; return $ this -> getEnv ( $ name ) ; }
docstring: Read an HTTP header from the Request information.
  
  If the header is not defined in the request, this method
  will fallback to reading data from $_SERVER and $_ENV.
  This fallback behavior is deprecated, and will be removed in 4.0.0
  
  @param string $name Name of the header you want.
  @return string|null Either null on no header being set or the value of the header.
  @deprecated 4.0.0 The automatic fallback to env() will be removed in 4.0.0, see getHeader()
docstring_tokens: Read an HTTP header from the Request information .