rjwoodhead / elm-life

Conway's Game of Life, implemented in Elm

Conway's Game of Life in Elm

I wrote this implementation of Conway's Life as a way to learn more about programming in Elm. As such it has more than the usual number of comments, which hopefully will be both helpful to other newbies and amusing to more experienced hands.

A live version of the app can be found here: http://www.madoverlord.com/Elm/Life/#

Features List

• Single-step or free-run life generations at various speeds. Board can be set to automatically expand or have edges that wrap.
• Edit, shift, rotate, minimize, zoom, clear and "soup" the board.
• Import boards in .cell and .rle formats, export in .cell.
• Prestored patterns.
• Help (teal ? icon).
• Detects if running on a touch device and responds accordingly.
• Autoresizes.

Things I Learned

I have put comments in the code regarding features of Elm that I learned about while doing this project. This includes:

• Detecting when user is on a touch-based device.
• Doing global to local mouse coordinate conversion.
• Tracking the mouse (and basic Json decoding).
• Defining local functions inside let blocks (and their scoping rules).
• Generating random numbers.
• Setting multiple variables using tuples (and the _ pattern-matching placeholder).
• head :: tail list pattern matching.
• SVG generation.
• More than I wanted to about Bootstrap.css.

Setup

1. Run npm install to install the build process dependancies.
2. Run npm install gulp -g to install the gulp executable globally.
3. Run elm package install to install the elm dependancies.

Start Build Process

1. Run gulp to start the build process.

Running on your local machine

Load http://localhost:4000/ in your browser.

Credit where Credit is Due

http://getbootstrap.com/ -- Documentation on Bootstrap.css

http://danielstern.ca/range.css/#/ -- Tool for customizing Bootstrap sliders

http://stackoverflow.com/questions/40269494/elm-adding-click-events-to-svg-elements-doesnt-work-is-this-possible -- insights on converting mouse locations from window-global to element-relative.

https://sourceforge.net/p/golly/discussion/467856/thread/2ea0e461/ -- optimal soup density

Thanks to @jessta and others on the Elm-slack #beginners channel for help.