code: func yaml_parser_fetch_flow_collection_start(parser *yaml_parser_t, typ yaml_token_type_t) bool {
  	// The indicators '[' and '{' may start a simple key.
  	if !yaml_parser_save_simple_key(parser) {
  		return false
  	}
  
  	// Increase the flow level.
  	if !yaml_parser_increase_flow_level(parser) {
  		return false
  	}
  
  	// A simple key may follow the indicators '[' and '{'.
  	parser.simple_key_allowed = true
  
  	// Consume the token.
  	start_mark := parser.mark
  	skip(parser)
  	end_mark := parser.mark
  
  	// Create the FLOW-SEQUENCE-START of FLOW-MAPPING-START token.
  	token := yaml_token_t{
  		typ:        typ,
  		start_mark: start_mark,
  		end_mark:   end_mark,
  	}
  	// Append the token to the queue.
  	yaml_insert_token(parser, -1, &token)
  	return true
  }
docs: // Produce the FLOW-SEQUENCE-START or FLOW-MAPPING-START token.