scalaz-stream is a streaming I/O library. The design goals are compositionality, expressiveness, resource safety, and speed. The design is meant to supersede or replace older iteratee or iteratee-style libraries.
The library supports a number of other interesting use cases:
- Zipping and merging of streams: A streaming computations may read from multiple sources in a streaming fashion, zipping or merging their elements using a arbitrary Tee. In general, clients have a great deal of flexibility in what sort of topologies they can define--source, sinks, and effectful channels are all first-class concepts in the library.
- Dynamic resource allocation: A streaming computation may allocate resources dynamically (for instance, reading a list of files to process from a stream built off a network socket), and the library will ensure these resources get released in the event of normal termination or when errors occur.
- Nondeterministic and concurrent processing: A computation may read from multiple input streams simultaneously, using whichever result comes back first, and a pipeline of transformation can allow for nondeterminism and queueing at each stage.
- Streaming parsing (UPCOMING): A separate layer handles constructing streaming parsers, for instance, for streaming JSON, XML, or binary parsing. See the roadmap for more information on this and other upcoming work.
