What is the difference between the final and const modifiers in programming languages?

In the Dart language (used in Flutter), the modifiers final and const are used to declare immutable values but have different characteristics:

• final means that the variable can be assigned only once, but the assignment can occur at runtime. For example, the value can be obtained during the program's execution.

• const means that the variable's value is a compile-time constant, i.e., it is known and fixed before the program runs.

Example:

final DateTime now = DateTime.now(); // can be assigned only once, but the value is determined at runtime
const int maxCount = 100; // the value is known at compile time and will not change