Observable which implements a HashSet under the hood, using
equals as equality.
Observable will only emit an event, if that event is not yet found
within the underlying HashSet.
new Stream.fromIterable([1, 2, 1, 2, 1, 2, 3, 2, 1]) .listen((event) => print(event));
will emit: 1, 2, 3
equals must define a stable equivalence relation, and
hashCode must be consistent with
hashCode are omitted, the set uses the elements' intrinsic
Object.hashCode. If you supply one of
hashCode, you should generally also to supply the other.
Stream< T>stream) → Stream< T>
Transforms the provided
RS, RT>( ) → StreamTransformer< RS, RT>
StreamTransformer<RS, RT>view of this stream transformer. [...]inherited
Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
) → String
A string representation of this object. [...]