Randomized templating language DSL

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BSD3 licensed by Vanessa McHale
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Madlang DSL for generating random text

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This is the Madlang DSL for generating random text. There is also a vim plugin, available here.

It enables you to generate random templated text with very little effort or expertise.

It can be used for twitter bots and provides human-readable syntax for Markov chains often used in natural language processing.


An exmaple is worth a thousand words, so suppose you wanted to generate a mediocre fortune telling bot. You could write the following code:

:define person
    0.7 "A close friend will "
    0.3 "You will "
:define goodfortune
    0.2 person "make rain on the planet Mars"
    0.8 "nice things will happen today :)"
:define fortune
    0.5 "drink a boatload of milk"
    0.5 "get angry for no reason"
    0.8 person fortune
    0.2 goodfortune

There are two "statements" in madlang, :define and :return. :return is the main string we'll be spitting back, so there can be only one per file. :define on the other hand can be used to make multiple templates. These templates are combinations of strings (enclosed in quotes) and names of other templates.

Of course, you can't have a circular reference with names - if goodfortune depends on fortune while fortune depends on goodfortune, we end up with either no fortune or an infinite fortune. So we throw an error.

Using the libary

The main function you'll want to use is probably runFile; it reads a file and generates randomized text:

 λ:> runFile [] "test/templates/gambling.mad"

Haddock documentation of all available functionality is located here.



If you're on windows or linux, grabbing release binaries is probably the easiest. Find them here.


Download stack with

curl -sSL | sh

Then run stack install madlang and you'll get the madlang executable installed on your path.


To use it, try

 $ madlang run fortune-teller.mad

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

Syntax Highlighting

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

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