There are three fundamental types in streamly. They are streams (Streamly.Data.Stream), pipes (Streamly.Internal.Data.Pipe) and folds (Streamly.Data.Fold). Streams are sources or producers of values, multiple sources can be merged into a single source but a source cannot be split into multiple stream sources. Folds are sinks or consumers, a stream can be split and distributed to multiple folds but the results cannot be merged back into a stream source again. Pipes are transformations, a stream source can be split and distributed to multiple pipes each pipe can apply its own transform on the stream and the results can be merged back into a single pipe. Pipes can be attached to a source to produce a source or they can be attached to a fold to produce a fold, or multiple pipes can be merged or zipped into a single pipe.

import qualified Streamly.Internal.Data.Pipe as Pipe