madlang: Randomized templating language DSL

[ bsd3, library, program, web ] [ Propose Tags ]

Madlang is a text templating language written in Haskell, meant to explore computational creativity and generative literature.

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Dependencies ansi-wl-pprint, base (>=4.8 && <5), composition, composition-extra, containers, directory, file-embed, madlang, megaparsec (>=6.0), microlens, MonadRandom, mtl, optparse-applicative, random-shuffle, template-haskell, text [details]
License BSD-3-Clause
Copyright Copyright: (c) 2016-2017 Vanessa McHale
Author Vanessa McHale
Category Web
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Source repo head: darcs get
Uploaded by vmchale at Fri Oct 6 04:03:04 UTC 2017
Distributions NixOS:
Executables madlang
Downloads 15182 total (1133 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2017-10-06 [all 1 reports]
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Readme for madlang-

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Madlang DSL for generating random text

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This is the Madlang DSL for generating text. You specify a template, and Madlang will create randomized text from the template.

Madlang is an interpreted language, written in Haskell. It runs from the command line, but also provides a Haskell library that can be integrated into other projects, compiled to a web app, or used as an EDSL.

There is also a vim plugin for syntax highlighting, available here.

It can be used for twitter bots (among other things) and provides human-readable syntax for generating text.


# Madlang is a declarative language. The most basic component is a function, viz.
:define coinFlip
    1.0 "heads"
    1.0 "tails"

:define die
    1.0 "1"
    1.0 "2"
    1.0 "3"
    1.0 "4"
    1.0 "5"
    1.0 "6"

# Madlang also has categories, that is, a collection of functions that can be
# bundled together
:category gambling

# :return declarations handle the actual output
    0.7 gambling
    0.3 gambling.to_upper # .to_upper is a modifier which make the whole string uppercase


There are two keywords in madlang you'll use most: :define and :return. :return is the main string we'll be spitting back; there can be only one per file. :define on the other hand can be used to make functions. These functions are combinations of templates, organizing pairs of weights and strings.

There is a Shakespearean insult generator demo available in demo/shakespeare.mad




If you're on linux or mac, you can get up-to-date binaries via nix.

Download nix with

curl | sh

From there, nix-env -i madlang will install the proper executables.


Download stack with

curl -sSL | sh

Then run stack install madlang --resolver nightly and you'll get the madlang executable installed on your path. This may take a bit of time, as it will build all dependencies of madlang first.


To use it, try

 $ madlang run demo/shakespeare.mad

You can do madlang --help if you want a couple other options for debugging.

Using the Haskell library

One function you might want to use is runFile; it reads a file and generates randomized text:

 λ:> runFile [] "demo/shakespeare.mad"
 "Thou hasty-witted gleeking puttock!"

To use the library as an EDSL, there are two options: splicing in a file or using a quasi-quoter, viz.

demo :: IO T.Text
demo = run
    $(madFile "demo/shakespeare.mad")

demo :: IO T.Text
demo = run [|madlang
:define f
    1.0 "heads"
    1.0 "tails"
    1.0 f|]

Haddock documentation of all library functionality is located here.

Syntax Highlighting

Syntax highlighting for the DSL is provided in the vim plugin here. It includes integration with syntastic.