Getting started with HaskellDO

*This page is based on the original README.md file for Theam’s HaskellDO repo *

HaskellDO is a Haskell code editor, centered around interactive development.

Usage

The only 3rd-party requirement to run HaskellDO is Stack and NodeJS.

Before proceeding, run a npm install -g purescript pulp bower to install the required NodeJS binaries.

Clone this repository, and from the root of the project run:

make deps for installing the required dependencies, and

make build-all-<platform>

Where <platform> is one of:

  • windows
  • linux
  • osx

Choose accordingly to your platform.

Initializing a project

Begin by creating a new Stack project.

stack new your_project_name

Fire up HaskellDO by running make run from the root of the project, it will ask you to open a Stack project. Navigate to the root of the project you just created and open that folder.

Main interface

Let’s begin by adding a text cell for documenting our analysis:

Imgur

HaskellDO’s text editor is based on SimpleMDE for handling the editing and rendering of the “documentation” part of our code.

It supports all the features that you would expect from a normal markdown editor, including image embedding.

  • Do a single click out of the editor to render the current text
  • Do a double click inside of the editor to come back to the text editing view.

Imgur

Now, it’s time to work with some code, let’s insert a code cell. In it, we write regular Haskell code, like we would do in a normal Haskell module.

In fact, our whole page is just a Haskell file that can be used in any Haskell, project. No need to export/import!

Imgur

Now we have to try our new algorithm we spent hours researching on. No, we do not have to spawn a stack ghci or a stack repl. HaskellDO manages that for us and reloads the code each time we ask it to evaluate some expression.

Just click on the toggle console button and press return on it to enable it.

After writing your expression, press return twice to get the result written on screen.

Imgur

But, what does our real module file look like? Let’s see the contents of our Main.hs file:

-- # Analyzing dog cuteness with genetic algorithms
--
-- After going **through thorough and tough thoughts**, we decided to use a simple example.

a = [1..20]
b = f <$> a

f :: Int -> Int
f x = x * 3 + 4

Just regular Haskell! Ready for deployment!