Returns a random element of the set if it is nonEmpty otherwise throws
IllegalArgumentException.
Returns a random element of the set if it is nonEmpty otherwise throws
IllegalArgumentException.
a random generator; it is essential that random be instantiated
by the caller just once for any sequence of calls
Finds an entry in the collection based on toMatch's hashCode and a correspondence
function but not on the argument type.
Finds an entry in the collection based on toMatch's hashCode and a correspondence
function but not on the argument type.
a value not necessarily of type A; the entry to be searched for
must have the same hashCode and be equal to this argument
function returning whether a given entry corresponds to other
the entry corresponding to toMatch or null if not contained
Returns a lazily filtered immutable Set.