What is the difference between the “const” and “final” keywords in Dart?

Question

What is the difference between const and final keyword in Dart?

Answer 1

my understand

const means its initial value is must be fixed, can not be a dynamic value;

final means its initial value is must be fixed but can be a dynamic value, equal to the var with a fixed value.

code demos

void main() {
  const sum = 1 + 2;
  // const can not change its value
  print("sum = ${sum}");
  // Const variables must be initialized with a constant value.
  const time = new DateTime.now();
  // Error: New expression is not a constant expression.
  print("time = ${time}");
}

// new DateTime.now();
// dynamic timestamp

void main() {
  final sum = 1 + 2;
  // final can not change its value
  print("sum = ${sum}");
  final time = new DateTime.now();
  // final === var with fixed value
  print("time = ${time}");
}

refs

https://dart.dev/guides/language/language-tour#final-and-const