DefaultIfEmptyStreamTransformer<S> class

Emit items from the source Stream, or a single default item if the source Stream emits nothing.

Example

Stream.empty()
  .transform(DefaultIfEmptyStreamTransformer(10))
  .listen(print); // prints 10
Inheritance
  • Object
  • StreamTransformerBase<S, S>
  • DefaultIfEmptyStreamTransformer

Constructors

DefaultIfEmptyStreamTransformer(S defaultValue)
Constructs a StreamTransformer which either emits from the source Stream, or just a defaultValue if the source Stream emits nothing.

Properties

defaultValue → S
The event that should be emitted if the source Stream is empty
final
hashCode → int
The hash code for this object. [...]
read-only, inherited
runtimeType → Type
A representation of the runtime type of the object.
read-only, inherited

Methods

bind(Stream<S> stream) → Stream<S>
Transforms the provided stream. [...]
override
cast<RS, RT>() → StreamTransformer<RS, RT>
Provides a StreamTransformer<RS, RT> view of this stream transformer. [...]
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
toString() → String
Returns a string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator. [...]
inherited