dart 3.0_record

readme.md

�dart 3.0_record

Created with <3 with dartpad.dev.

main.dart

// record

// 순서와 타입을 보장해 주는 자료형

void main() {
  final result = nameAndAge({
    'name': '하하',
    'age': 20,
  });

  print(result);

  print(result.$1);
  print(result.$2);
  
  
  print('-------------');
  final result2 = getUsersWithType();
  
  for(final item in result2){
    print(item.$1);
    print(item.$2);
  }
  
  print('-------------');
  
  final result3 = getUsersWithType2();
  
  for(final item in result3){
    print(item.$1);
    print(item.$2);
  }
  
  print('-------------');
  
  final result4 = getUsersWithType3();
  
  for(final item in result4){
    print(item.name);
    print(item.age);
  }
}


/// record 
(String, int) nameAndAge(Map<String, dynamic> json) {
  return (json['name'] as String, json['age'] as int);
}


// 전통적인  map 방식
List<Map<String, dynamic>> getUsers() {
  return [
    {
      'name': '하하',
      'age': 20,
    },
    {
      'name': 'ghgh',
      'age': 10,
    },
  ];
}


// list record
List<(String, int)> getUsersWithType() {
  return [
    (
      '하하',
      20,
    ),
    (
      'ghgh',
      10,
    ),
  ];
}

//list record with naming
List<(String name, int age)> getUsersWithType2(){
   return [
    (
      '하하',
      20,
    ),
    (
      'ghgh',
      10,
    ),
  ];
}

//list record with named param
List<({String name, int age})> getUsersWithType3(){
   return [
    (
      name: '하하',
      age :20,
    ),
    (
      name: 'ghgh',
      age: 10,
    ),
  ];
}