New post: Declaring bankruptcy on AoC 2023

content/posts/20230309-aoc2022.md

@@ -1,6 +1,6 @@
 title: Advent of Code 2022 was fun!
 slug: aoc2022
-tags: programming, go
+tags: programming, go, advent-of-code
 date: 2023-03-09
 
 This was the first year I participated in [Advent of Code].

content/posts/20240109-aoc-bankruptcy.md

@@ -0,0 +1,119 @@
+title: Declaring bankruptcy on Advent of Purescript 2023
+tags: programming, purescript, advent-of-code
+slug: aoc2023-bankruptcy
+date: 2024-01-09
+
+Advent of Code is a [fun challenge] and this year I decided to attempt
+[solving it in Purescript][solutions]. Today I'm declaring this attempt a
+failure. This post will serve as a postmortem.
+
+[fun challenge]: {filename}/posts/20230309-aoc2022.md
+[solutions]: https://sio.github.io/advent-of-code/2023/
+
+
+## Choosing Purescript
+
+Last year I solved my first Advent of Code using Go. It was fun and I knew
+immediately that I will come back for the next AoC. I also knew that I won't
+be solving it using the same language - learning on the go (pun intended)
+contributed significantly to my enjoyment of AoC 2022.
+
+In November 2023 I listened to an [old podcast] where Richard Feldman
+evangelises Elm programming language. I got interested and initially decided
+to use Elm for the upcoming Advent of Code. While I was learning the basics of
+the language I also learned about the ongoing old controversy in Elm community
+related to how its BDFL handles communication and development. I decided that
+that's too much drama for my liking and that it has too little hope of
+resolving anytime soon
+- and that it's better to stay away from Elm.
+
+That's how I ended up with [Purescript]. It was probably the only other
+frontend language that offered functional programming with a strong type
+system and a [nice UI framework][Halogen]. I hoped that using an
+unconventional language would introduce me to frontend development without
+dealing with unpleasant Javascript ecosystem.
+
+[old podcast]: https://corecursive.com/teaching-fp-with-richard-feldman/
+[Purescript]: https://www.purescript.org/
+[Halogen]: https://github.com/purescript-halogen/purescript-halogen
+
+
+## Learning Purescript
+
+My only prior experience with functional programming was Microsoft's Power
+Query [M language]({tag}/m) which is rather narrowly focused on data
+processing and is not a general purpose language.
+
+So, with effectively zero prior knowledge I started learning from [The
+Purescript book](https://book.purescript.org/) but quickly switched to
+[Functional Programming Made Easier](https://leanpub.com/fp-made-easier) by
+Charles Scalfani - the former was too fast paced for me.
+Scalfani's book was an enjoyable read even if a little too verbose.
+I did not follow author's advice to type out and run all code snippets from
+the book - that may have contributed to my eventual failure but I don't think
+that it was a major factor.
+
+
+## Failing Purescript
+
+I enjoyed solving small textbook problems in Purescript. It's a very nice
+language. Here are the things I liked most about it:
+
+- Separation of pure and effectful functions
+- Fearless refactoring
+- Clean and readable syntax
+- Pattern matching with exhaustiveness checking
+- Function currying, tail call optimisation and other FP niceties
+- Type system
+
+I had no problems with understanding recursion, currying, pattern matching,
+etc. I had relatively little problems with understanding monads and related
+concepts.
+
+My problem was that these nice abstract concepts just did not translate in my
+head to applicable programming techniques. Simple practical tasks tripped me
+up hard.
+
+Parsing text was painful. For the first AoC puzzle I decided to [tough it out]
+with a bespoke char based parser even though I vaguely understood that there
+should be a monad based parser combinator library for that. That vague
+knowledge was not provided by any of these books, I've picked it up
+accidentally from some random blog post on the web.
+
+For the second AoC day I [used the proper library]. It was better but still
+felt unnecessarily difficult. When third day's puzzle called for a parser not
+based on regular grammar my mind just blanked out. I was loaded up to the brim
+with pure theory and I lacked practical knowledge to apply it.
+
+All this time while I was struggling with text parsing the actual tasks I
+picked up Purescript for (frontend experiments and puzzle solving) were
+deprioritized to background. I have to commend Purescript and Halogen on this
+because if it was anything less than straightforward none of UI and/or puzzle
+solutions would get done - I just barely devoted any time to that.
+
+The project got stalled. I was reluctant to finish the last chapters of
+Scalfani's book because I was confident that they won't provide me with
+practical knowledge I was lacking. I was hesitant to go web diving for new,
+more practical learning materials because I wasn't sure they exist -
+Purescript community is rather small, and most learning resources are
+enumerated in multiple places. I evaluated those lists the first time I looked.
+I probably should've gone looking for more generic functional programming
+knowledge - and that would blow my free time budget.
+
+So I'm just declaring bankruptcy on this project.
+
+[tough it out]: https://github.com/sio/advent-of-code/blob/18c766f757eb71af581ffdeabba056586cf1bd3b/aoc2023/src/Day01/Solve.purs#L137-L147
+[used the proper library]: https://github.com/sio/advent-of-code/blob/18c766f757eb71af581ffdeabba056586cf1bd3b/aoc2023/src/Day02/Solve.purs#L112-L120
+
+
+## Conclusion
+
+Even though I failed to cowboy my way into Purescript I still got [the
+solutions to first two days][solutions] of Advent of Code to show off -
+all logic executed client side, all UI generated on demand, all type safe and
+checked at compile time.
+
+I could probably pour more effort, practise more, find new learning resources
+- and complete the remaining challenges. I'm stubborn enough to see this through.
+But my hobby time is not unlimited and there are other projects waiting -
+I'm certain I will enjoy some of them more.