Conway's Game of Life

 The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician John Horton Conway in 1970.  See Wikipedia entry. The idea is that cells grow or die according to a simple set of rules:

• Any live cell with fewer than two live neighbors dies, as if by under-population.

• Any live cell with two or three live neighbors lives on to the next generation.

• Any live cell with more than three live neighbors dies, as if by overcrowding.

• Any dead cell with exactly three live neighbors becomes a live cell, as if by reproduction.

This implementation illustrates how the higher order method 'foldLeft' can be used in place of a 'for' loop (not to be confused with for expressions) to iterate over the cell population. This is a fundamental concept in functional programming. Take it easy if it doesn't make sense right now. It will eventually. I took a full blown course to get to learn all that from a wonderful teacher: Eric Meijer's intro to teaching functional programming with Haskell. You can study the whole course in YouTube, or from the archives of edx.org.

Click here and start the fun! http://ikojo.in/sf/pUmyQ66/9

Or start with a simpler pattern and see a steady-state: http://ikojo.in/sf/pUmyQ66/10

Or, see a seemingly more complicated starting point: http://ikojo.in/sf/pUmyQ66/13

But, run it to see how short-lived it is: http://ikojo.in/sf/pUmyQ66/12

Check this one out, called block1: http://ikojo.in/sf/pUmyQ66/14

Now run it and enjoy: http://ikojo.in/sf/pUmyQ66/15

It will eventually converge to a steady-state, but it takes a while. So, run it faster: http://ikojo.in/sf/pUmyQ66/16

Now, go back or forward and read some more musings about it here (search for Game of Life in the page, it's towards the bottom...