void main() {
  print('--- 1. forEach() ---');
  // 1. forEach() | Runs a function on each element in the list
  var fruits = ['banana', 'pineapple', 'watermelon'];
  fruits.forEach((fruit) => print(fruit)); // => banana pineapple watermelon

  print('--- 2. map() ---');
  // 2. map() | Produces a new list after transforming each element in a given list
  var mappedFruits = fruits.map((fruit) => 'I love $fruit').toList();
  print(mappedFruits); // => ['I love banana', 'I love pineapple', 'I love watermelon']


  print('--- 3. contains() ---');
  // 3. contains() | Checks to confirm that the given element is in the list
  var numbers = [1, 3, 2, 5, 4];
  print(numbers.contains(2)); // => true

  print('--- 4. sort() ---');
  // 4. sort() | Order the elements based on the provided ordering function
  numbers.sort((num1, num2) => num1 - num2);
  print(numbers); // => [1, 2, 3, 4, 5]

  print('--- 5. reduce(), fold() ---');
  // 5. reduce(), fold() | Compresses the elements to a single value, using the given function
  var sum = numbers.reduce((current, next) => current + next);
  print(sum); // => 15

  const initialValue = 10;
  var sum2 = numbers.fold(initialValue, (current, next) => current + next);
  print(sum2); // => 25

  print('--- 6. every() ---');
  // 6. every() | Confirms that every element satisfies the test
  List<Map<String, dynamic>> users = [
    { "name": 'Jane', "age": 18 },
    { "name": 'Jim', "age": 21 },
    { "name": 'Mary', "age": 23 },
  ];
  var is18AndOver = users.every((user) => user["age"] >= 18);
  print(is18AndOver); // => true

  var hasNamesWithJ = users.every((user) => user["name"].startsWith('J'));
  print(hasNamesWithJ); // => false

  print('--- 7. where(), firstWhere(), singleWhere()');
  // 7. where(), firstWhere(), singleWhere() | Returns a collection of elements that satisfy a test.
  // firstWhere() returns the first match in the list, while singleWhere() returns the first match provided there is exactly one match.
  var over21s = users.where((user) => user["age"] > 20);
  print(over21s.length); // => 1

  var under18s = users.singleWhere((user) => user["age"] < 18, orElse: () => null);
  print(under18s); // => null

  var nameJ = users.firstWhere((user) => user["name"].startsWith('J'), orElse: () => null);
  print(nameJ); // => {name: Jane, age: 18}

  print('--- 8. take(), skip() ---');
  // take(), skip() | Returns a collection while including or skipping elements
  var fiboNumbers = [1, 2, 3, 5, 8, 13, 21];
  print(fiboNumbers.take(3).toList()); // => [1, 2, 3]
  print(fiboNumbers.skip(5).toList()); // => [13, 21]
  print(fiboNumbers.take(3).skip(2).take(1).toList()); // => [3]

  print('--- 9. List.from() ---');
  // List.from() | Creates a new list from the given collection
  var clonedFiboNumbers = List.from(fiboNumbers);
  print(clonedFiboNumbers); // => [1, 2, 3, 5, 8, 13, 21]

  print('--- 10. expand() ---');
  // expand() | Expands each element into zero or more elements
  var pairs = [[1, 2], [3, 4]];
  var flattened = pairs.expand((pair) => pair).toList();
  print('Flattened result: $flattened'); // => [1, 2, 3, 4]

  var input = [1, 2, 3];
  var duplicated = input.expand((i) => [i, i]).toList();
  print(duplicated); // => [1, 1, 2, 2, 3, 3, 4, 4]
}