contains method
- E object
override
Checks if object
is in the queue.
Returns true if the element is found.
Uses the Object.== of elements in the queue to check
for whether they are equal to object
.
Equal objects objects must have the same priority
according to the comparison function.
That is, if a == b
then comparison(a, b) == 0
.
If that is not the case, this check might fail to find
an object.
Implementation
@override
bool contains(E object) => _locate(object) >= 0;