Dart Final vs. Const

dartFinalConst.dart

// https://dartpad.dev/e31c87278033dbaf3bb4d55bfa8fd721
// e31c87278033dbaf3bb4d55bfa8fd721
// [Dart Final vs. Const](https://www.appbrewery.co/courses/548873/lectures/9988849)
void main() {
  
  // int myNumber = 1; // if we want no change after this
  // use `const` OR `final`
  // const int myConst = 2;
  // final int myFinal = 3;
  
  // myConst = 4; // error Constant variables can't be assigned a value - docs "a compile-time constant"
  
  // myFinal = 5; // error The final variable 'myFinal' can only be set once
  
  // myNumber = 6;
  // print('$myNumber, $myConst, $myFinal'); // 6, 2, 3
  
  // diffs between [Final and const](https://dart.dev/guides/language/language-tour#final-and-const)
  
  final DateTime myFinal = DateTime.now(); // OK runtime 
  print('$myFinal'); // OK runtime 2020-07-14 09:54:57.315
  
  /*
  const DateTime myConst = DateTime.now(); // BEFORE run-time compiler says 2 errors: e1 The constructor being called isn't a const constructor - e2 Const variables must be initialized with a constant value
  print('$myConst'); // OK runtime 2020-07-14 09:54:57.315
  */
}