contains method

bool contains(T element)

Checks if element is a member of this set.

Notation: x ∈ A

Returns true if element is in the set, false otherwise.

Example:

final set = CustomSet<int>([1, 2, 3]);
print(set.contains(2)); // Output: true
print(set.contains(5)); // Output: false

Implementation

bool contains(T element) => _elements.contains(element);