original_string: protected function computeCacheControlValue()
      {
          if (!$this->cacheControl && !$this->has('ETag') && !$this->has('Last-Modified') && !$this->has('Expires')) {
              return 'no-cache, private';
          }
  
          if (!$this->cacheControl) {
              // conservative by default
              return 'private, must-revalidate';
          }
  
          $header = $this->getCacheControlHeader();
          if (isset($this->cacheControl['public']) || isset($this->cacheControl['private'])) {
              return $header;
          }
  
          // public if s-maxage is defined, private otherwise
          if (!isset($this->cacheControl['s-maxage'])) {
              return $header.', private';
          }
  
          return $header;
      }
code: protected function computeCacheControlValue()
      {
          if (!$this->cacheControl && !$this->has('ETag') && !$this->has('Last-Modified') && !$this->has('Expires')) {
              return 'no-cache, private';
          }
  
          if (!$this->cacheControl) {
              // conservative by default
              return 'private, must-revalidate';
          }
  
          $header = $this->getCacheControlHeader();
          if (isset($this->cacheControl['public']) || isset($this->cacheControl['private'])) {
              return $header;
          }
  
          // public if s-maxage is defined, private otherwise
          if (!isset($this->cacheControl['s-maxage'])) {
              return $header.', private';
          }
  
          return $header;
      }
code_tokens: protected function computeCacheControlValue ( ) { if ( ! $ this -> cacheControl && ! $ this -> has ( 'ETag' ) && ! $ this -> has ( 'Last-Modified' ) && ! $ this -> has ( 'Expires' ) ) { return 'no-cache, private' ; } if ( ! $ this -> cacheControl ) { // conservative by default return 'private, must-revalidate' ; } $ header = $ this -> getCacheControlHeader ( ) ; if ( isset ( $ this -> cacheControl [ 'public' ] ) || isset ( $ this -> cacheControl [ 'private' ] ) ) { return $ header ; } // public if s-maxage is defined, private otherwise if ( ! isset ( $ this -> cacheControl [ 's-maxage' ] ) ) { return $ header . ', private' ; } return $ header ; }
docstring: Returns the calculated value of the cache-control header.
  
  This considers several other headers and calculates or modifies the
  cache-control header to a sensible, conservative value.
  
  @return string
docstring_tokens: Returns the calculated value of the cache - control header .