streamly/INSTALL.md

Using streamly package

If you are new to Haskell please take a look at Haskell Getting Started Guide.

The following instructions assume that you are using a shell on a POSIX system. On Windows you need a shell under msys, some of the commands may have slight differences.

Which version to use?

• Latest stable release is available on Hackage.
• Latest development version is available on github.

If you are using stack or nix please make sure to add the latest version from Hackage to your tool configuration.

Recommended build options

See recommended compilation options here.

Using with cabal

Make sure you have cabal version 3.0 or later installed and you have ghc available in your PATH. Refresh your package list:

$ cabal update

Create a directory for isolated builds:

$ mkdir streamly-play

Create a .cabal file:

$ cd streamly-play
$ cabal init --minimal --dependency base --dependency streamly

You can add any other dependencies as well later on by editing the build-depends section of the cabal file.

Using hackage version in repl

Run repl with the latest version from Hackage:

$ cabal repl --build-depends streamly
GHCi, version 8.8.3: https://www.haskell.org/ghc/  :? for help
[1 of 1] Compiling Main             ( Main.hs, interpreted )
Ok, one module loaded.
*Main> S.drain $ S.mapM print $ S.fromList [1..3]
1
2
3
*Main>

Run repl with a specific version from Hackage:

$ cabal repl --build-depends streamly==0.7.2

Using github version in repl

Create a cabal.project file with the following contents:

packages: .
source-repository-package
  type: git
  location: https://github.com/composewell/streamly
  tag: master

Run repl:

$ cabal repl

Hello World!

Edit Main.hs as follows:

module Main where

import qualified Streamly.Prelude as S

main :: IO ()
main = S.drain $ S.mapM print $ S.fromList [1..3]

Build and run:

$ cabal run