Lists

A List holds an ordered collection of values: var numbers = [1, 2, 3, 4, 5];.

Example: transforming a list with map()

void main() {
  var numbers = [1, 2, 3, 4, 5];
  var doubled = numbers.map((n) => n * 2).toList();
  print(doubled);
}

[2, 4, 6, 8, 10]

.map() transforms every item using the function you pass it — here, the arrow function from the previous lesson — and returns a new, lazily-evaluated sequence, which .toList() then converts into a real, concrete list. This is the same underlying idea as JavaScript's .map() array method, just Dart's particular spelling of it (with that extra .toList() step Dart requires that JavaScript doesn't).