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haskellscript

Version 0.2.3 revision 0 uploaded by seanparsons.

Package meta

Synopsis
Command line tool for running Haskell scripts with a hashbang.
Description

This tool provides the ability to script in a shell with Haskell (including dependencies) the same way that has been possible with bash scripts or Python.

Examples

Print out JSON constructed with Aeson

https://github.com/seanparsons/haskellscript/blob/master/Example.hs

Lookup weather for your current IP address

https://github.com/seanparsons/haskellscript/blob/master/WeatherExample.hs

Prerequisites

A sandbox capable install of Cabal.

Howto

The script falls into three main parts:

  • The hashbang first line:

#!/usr/bin/env haskellscript

  • Dependencies (potentially including versions):

--#aeson

  • The code:

import Data.Aeson
import Data.ByteString.Lazy hiding (putStrLn, unpack)
import Data.Text
import Data.Text.Encoding
jsonExample = object ["Test" .= True, "Example" .= True]
main = putStrLn $ unpack $ decodeUtf8 $ toStrict $ encode jsonExample

Note that because the dependencies specified are hashed to enable re-use it's worth specifying exact versions across multiple scripts to prevent the version used being quite old after a while.

Author
Sean Parsons
Bug reports
http://github.com/seanparsons/haskellscript/issues
Category
Development
Copyright
Copyright (C) 2015 Sean Parsons
Homepage
http://github.com/seanparsons/haskellscript/
Maintainer
github@futurenotfound.com
Package URL
n/a
Stability
n/a

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