The equality operator.
The default behavior for all Objects is to return true if and
only if this
and other
are the same object.
Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:
Total: It must return a boolean for all arguments. It should never throw
or return null
.
Reflexive: For all objects o
, o == o
must be true.
Symmetric: For all objects o1
and o2
, o1 == o2
and o2 == o1
must
either both be true, or both be false.
Transitive: For all objects o1
, o2
, and o3
, if o1 == o2
and
o2 == o3
are true, then o1 == o3
must be true.
The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.
If a subclass overrides the equality operator it should override the hashCode method as well to maintain consistency.
bool operator ==(dynamic other) =>
// Can't change argument type to `Object` since subclasses inherit it
// and uses their argument dynamically.
other is Rectangle &&
left == other.left &&
top == other.top &&
right == other.right &&
bottom == other.bottom;