original_string: public static function instance_by_id($id, $strictness = MUST_EXIST) {
          global $DB;
  
          if (get_called_class() !== 'context' and get_called_class() !== 'context_helper') {
              // some devs might confuse context->id and instanceid, better prevent these mistakes completely
              throw new coding_exception('use only context::instance_by_id() for real context levels use ::instance() methods');
          }
  
          if ($id == SYSCONTEXTID) {
              return context_system::instance(0, $strictness);
          }
  
          if (is_array($id) or is_object($id) or empty($id)) {
              throw new coding_exception('Invalid context id specified context::instance_by_id()');
          }
  
          if ($context = context::cache_get_by_id($id)) {
              return $context;
          }
  
          if ($record = $DB->get_record('context', array('id'=>$id), '*', $strictness)) {
              return context::create_instance_from_record($record);
          }
  
          return false;
      }
code: public static function instance_by_id($id, $strictness = MUST_EXIST) {
          global $DB;
  
          if (get_called_class() !== 'context' and get_called_class() !== 'context_helper') {
              // some devs might confuse context->id and instanceid, better prevent these mistakes completely
              throw new coding_exception('use only context::instance_by_id() for real context levels use ::instance() methods');
          }
  
          if ($id == SYSCONTEXTID) {
              return context_system::instance(0, $strictness);
          }
  
          if (is_array($id) or is_object($id) or empty($id)) {
              throw new coding_exception('Invalid context id specified context::instance_by_id()');
          }
  
          if ($context = context::cache_get_by_id($id)) {
              return $context;
          }
  
          if ($record = $DB->get_record('context', array('id'=>$id), '*', $strictness)) {
              return context::create_instance_from_record($record);
          }
  
          return false;
      }
code_tokens: public static function instance_by_id ( $ id , $ strictness = MUST_EXIST ) { global $ DB ; if ( get_called_class ( ) !== 'context' and get_called_class ( ) !== 'context_helper' ) { // some devs might confuse context->id and instanceid, better prevent these mistakes completely throw new coding_exception ( 'use only context::instance_by_id() for real context levels use ::instance() methods' ) ; } if ( $ id == SYSCONTEXTID ) { return context_system :: instance ( 0 , $ strictness ) ; } if ( is_array ( $ id ) or is_object ( $ id ) or empty ( $ id ) ) { throw new coding_exception ( 'Invalid context id specified context::instance_by_id()' ) ; } if ( $ context = context :: cache_get_by_id ( $ id ) ) { return $ context ; } if ( $ record = $ DB -> get_record ( 'context' , array ( 'id' => $ id ) , '*' , $ strictness ) ) { return context :: create_instance_from_record ( $ record ) ; } return false ; }
docstring: Get a context instance as an object, from a given context id.
  
  @static
  @param int $id context id
  @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found;
  MUST_EXIST means throw exception if no record found
  @return context|bool the context object or false if not found
docstring_tokens: Get a context instance as an object from a given context id .