code: func (t *Iterator) Consume(cnt int) {
  	for i := 0; i < cnt; i++ {
  		token := t.Next()
  		if token.Type == tError || token.Type == tEOF {
  			t.Backup()
  			break
  		}
  	}
  }
docs: // Consume is a convencience method to consume the next n tokens,
  // but back off Errors and EOF.