forced me to learn stuff like: how to manage a monad transformer stack, how to make http requests, how to parse and serialize json, how to write to a database, etc..
I am currently just before this stage. I can use Haskell for stuff like projecteuler.net problems but I haven't written a single useful, real-world program without copy-pasting some code.
I tried doing something with http requests to an API for stock trading but I failed to understand how to make a request. There are a few packages but they all have their flaws (e.g. no https) and aren't really developed that much.
My question is: did you write all these things with mostly only the Prelude of Haskell or did you use packages for all those things you listed (http requests, json data, databases etc.)?
I'd love some pointers in the right direction for http requests as well as maybe ideas for initial real-world project ideas that are exciting (I don't care for the standard ones you find online).
Yeah, the goal was (rather, is---I'm still working on it!) to learn more about real-world Haskell by actually learning how to use packages and forcing myself to read the Hackage docs, so for this project I pretty liberally import a new library whenever I need something.
The "req" package is very intuitive to use for requests, and plays nicely with "aeson" for parsing JSON. I'm also using "persistent" to manage a sqlite database.
For project ideas, try to scratch a personal itch. If you're solving a problem (or a daily frustration) that's important to you, you'll be more motivated to follow through! For me, I had been using the beets (https://beets.io/) command line tool to manage tags for my music library, but it isn't really optimized for my use case, and I thought I could do better. So I decided to write a cli [1] with Haskell to tag all my local music files with metadata from Discogs/MusicBrainz, modeled after the beets tagging loop. I'm also working on a more advanced tagging system that uses Datalog inference rules, inspired by a blog post [2].
Try using wreq[0] instead. Here's also a post[1] which describes someone else facing the same pains earlier that you're currently having. For anything to do with JSON, you need Aeson[2]. For working with databases, Persistent[3] and Esqueleto[4] (they're designed to work together) work great.
Comments
I am currently just before this stage. I can use Haskell for stuff like projecteuler.net problems but I haven't written a single useful, real-world program without copy-pasting some code.
I tried doing something with http requests to an API for stock trading but I failed to understand how to make a request. There are a few packages but they all have their flaws (e.g. no https) and aren't really developed that much.
My question is: did you write all these things with mostly only the Prelude of Haskell or did you use packages for all those things you listed (http requests, json data, databases etc.)?
I'd love some pointers in the right direction for http requests as well as maybe ideas for initial real-world project ideas that are exciting (I don't care for the standard ones you find online).
Yeah, the goal was (rather, is---I'm still working on it!) to learn more about real-world Haskell by actually learning how to use packages and forcing myself to read the Hackage docs, so for this project I pretty liberally import a new library whenever I need something.
The "req" package is very intuitive to use for requests, and plays nicely with "aeson" for parsing JSON. I'm also using "persistent" to manage a sqlite database.
For project ideas, try to scratch a personal itch. If you're solving a problem (or a daily frustration) that's important to you, you'll be more motivated to follow through! For me, I had been using the beets (https://beets.io/) command line tool to manage tags for my music library, but it isn't really optimized for my use case, and I thought I could do better. So I decided to write a cli [1] with Haskell to tag all my local music files with metadata from Discogs/MusicBrainz, modeled after the beets tagging loop. I'm also working on a more advanced tagging system that uses Datalog inference rules, inspired by a blog post [2].
[1] https://github.com/benrbray/borscht-hs [2] https://dodisturb.me/posts/2018-12-25-The-Essence-of-Datalog...
Try using wreq[0] instead. Here's also a post[1] which describes someone else facing the same pains earlier that you're currently having. For anything to do with JSON, you need Aeson[2]. For working with databases, Persistent[3] and Esqueleto[4] (they're designed to work together) work great.
[0]: https://hackage.haskell.org/package/wreq
[1]: https://bitemyapp.com/blog/haskell-is-not-trivial-not-unfair...
[2]: https://artyom.me/aeson
[3]: https://hackage.haskell.org/package/persistent
[4]: https://hackage.haskell.org/package/esqueleto
Persistent is truly amazing. I don't think I've ever had such a smooth experience working with databases in any other language.