I remember trying to use Immutable.js back in the day. It's probably pretty great with Typescript these days, but I remember it was kinda hell with vanilla JS back then since I'd accidentally do things like assign `thing.foo = 42` instead of `thing.set('foo', 42)` and I'd comb through the code to see why it wouldn't work, and I remember not knowing when I had a JS object or a Record. All things fixed by Typescript, of course.
I'm slightly horrified by the memory leak that's casually introduced without even a remark as to the potential to cause a problem. I can't tell if I'm more horrified by the cavalier attitude or the fact that JavaScript makes having a global registry the only easy way to use an object of an arbitrary type as a key to Map.
But at the very least, if you're going to memoize immutable values, please do it in a way that allows garbage collection. JavaScript has WeakRef and FinalizationRegistry. (Why it doesn't provide the obvious WeakCache built on those is a mystery, though.)
The issues won't be visible on a toy example like making mazes a few hundred elements across, but if you use these techniques on real problems, you absolutely need to cooperate with the garbage collector.
If you enjoyed that, I have a blog post on generating mazes in Haskell (from over a decade ago!). The algorithm is very similar, but the code is written using "inductive graphs" and the post is really more of an intro to working with graphs in a purely functional style.
Kind of amusing and maybe telling that this article about implementing an algorithm functionally begins by explaining it in an iterative, mutational fashion.
Once you have the maze you need to solve it. JavaScript is a great environment for tinkering. If you would like to try, I made an online maze game for myself this year.
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[ 48.9 ms ] story [ 135 ms ] threadI remember trying to use Immutable.js back in the day. It's probably pretty great with Typescript these days, but I remember it was kinda hell with vanilla JS back then since I'd accidentally do things like assign `thing.foo = 42` instead of `thing.set('foo', 42)` and I'd comb through the code to see why it wouldn't work, and I remember not knowing when I had a JS object or a Record. All things fixed by Typescript, of course.
But at the very least, if you're going to memoize immutable values, please do it in a way that allows garbage collection. JavaScript has WeakRef and FinalizationRegistry. (Why it doesn't provide the obvious WeakCache built on those is a mystery, though.)
The issues won't be visible on a toy example like making mazes a few hundred elements across, but if you use these techniques on real problems, you absolutely need to cooperate with the garbage collector.
https://jelv.is/blog/Generating-Mazes-with-Inductive-Graphs
A Skeptic’s Guide To Functional Programming With JavaScript
https://jrsinclair.com/skeptics-guide
I’d recommend it for functional-curious JS devs like myself.
https://hypervariety.com/Amaze/