main.dart

//Step3
late String lateName;
// final int finalName; // error

void main() {
//Step 1
  final int x;
  const int y = 1;
  x = 8; // ok
  // y = 2; // error: Constant variables can't be assigned a value.
  // x = 9; // error: The final variable 'x' can only be set once.

//Step2
  var one = const [];
  one = const [1, 2, 3]; // ok
  // one[0] = 4; //Unsupported operation: Cannot modify an unmodifiable list

  final two = const [];
  // two = const [10, 3, 23]; // error

  const three = [];
  // three = const [10, 3, 23]; // error

//Step3
  final int finalName; // ok
// print(lateName);
// LateInitializationError: Field 'lateName' has not been initialized
  lateName = '#Flutter';
  print(lateName); // ok
}