pipes
is a clean and powerful stream processing library that lets you build
and connect reusable streaming components.
- Install the Haskell Platform
cabal install pipes
Then fire up ghci
:
$ ghci
Prelude> import Pipes
Prelude Pipes> import qualified Pipes.Prelude as P
... and echo standard input to standard output until you enter quit
.
Prelude Pipes P> run $ P.stdin >-> P.takeWhile (/= "quit") >-> P.stdout
Test[Enter]
Test
Apple[Enter]
Apple
quit[Enter]
Prelude P> -- Done!
The tutorial for version 4.0.0 is complete, and you can find the tutorial
here
until pipes-4.0.0
is on Hackage.
-
Concise API: Use simple commands like
for
,(>->)
,await
, andyield
-
Blazing fast: Implementation tuned for speed
-
Lightweight Dependency:
pipes
is small and compiles very rapidly, including dependencies -
Elegant semantics: Use practical category theory
-
ListT: Correct implementation of
ListT
that interconverts with pipes -
Bidirectionality: Implement duplex channels
-
Extensive Documentation: Second to none!
The pipes
library emphasizes the following three design precepts:
-
Emphasize elegance - Elegant libraries replace inelegant libraries
-
Theory everywhere - Principled design promotes intuitive behavior
-
Minimize dependencies - Small dependency profiles maximize portability
The core pipes
ecosystem consists of the following four libraries:
-
pipes
: The elegant, theoretically-principled core. -
pipes-concurrency
: Message passing and reactive programming -
pipes-parse
: Utilities for parsing streams -
pipes-safe
: Resource management and exception safety
These represent the core areas that I envision for pipes
. The latter three
libraries represent the more pragmatic face of the ecosystem and make design
tradeoffs where there is no known elegant solution.
The pipes
ecosystem is in the middle of a transition to use the new 4.0.0 API.
This version should be the last significant API change for the core pipes
library, although downstream libraries may still exhibit some API instability
for a couple of months as they experiment with a few new features enabled by the
4.0.0 API.
All development work currently focuses on transitioning downstream libraries to
use pipes-4.0.0
and building out the pipes
ecosystem.
The long term goal is to get pipes
into the Haskell platform and become the
basic building block for streaming APIs.
-
Contribute code
-
Build derived libraries
-
Write
pipes
tutorials
Copyright (c) 2012, 2013 Gabriel Gonzalez All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
-
Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
-
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
-
Neither the name of Gabriel Gonzalez nor the names of other contributors may be used to endorse or promote products derived from this software without specific prior written permission.
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