jordan VS learnyouahaskell.github.io

I'm having some trouble getting GHC to use a quantified constraint in my library jordan (Link is to the specific PR where the issue is arising, and is very much a WIP).

> Let’s say I wanted to introduce Jordan at work, as part of a drive for a Haskell web service. I’d have to explain to everybody what the hell Rank-N types are

If so, that's a problem of jordan's documentation. If it's documented with enough practical examples of how to get things done, and it's not buggy, no one needs to know about how it does it, or even why we have to write "forall" here. And I see from the article that it even uses generic so you can get instances derived for you (probably don't even have to add the RankNTypes pragma in your own files). Even the hand-written examples of https://github.com/AnthonySuper/jordan/blob/master/jordan/RE... don't seem to require any esoteric knowledge. But it's probably hard to write about Haskell without showing off all the fancy features that make things work under the hood :)

I remember following http://www.serpentine.com/wreq/tutorial.html years ago for work while starting out with Haskell. It introduced the absolute minimal stuff needed for lens (I didn't delve any deeper into lens than what the tutorial showed), and I was immediately productive. Now I took a quick look at the source of wreq and the first file I see has RankNTypes, GADT's, etc. and I never knew.

The github page for this project is located here. While I'm not gunning to replace Aeson or anything, I would really appreciate any feedback anybody has to offer!

Oh OK. Then yes get a good textbook for yourself. Learn you a Haskell for Great Good (I'd suggest: https://learnyouahaskell.github.io/ over the one in the sidebar) is free on the web. But buy a book and get it soon.

So we have LYAH, also there is O'Reilly book, which is a bit old but still mostly good, many people start with this book. After any of those three you can probably decide for yourself what to use to continue the study

You can find an exhaustive list on haskell.org/documentation, but I'd recommend Learn You A Haskell (LYAH), haskell.mooc.fi, or CIS 194.

There is a community edition of LYAH that's still being updated.

In case there are any beginners stumbling upon this I just want to repeat what I said on the Discord: This code example (at least the original code OP posted - it seems to have been edited since) originates from the terrible TutorialsPoint Haskell tutorial. It is outdated and comically wrong, please don't use it. If you're looking for free Haskell tutorials I'd suggest the Wikibook or Learn You a Haskell.

I'm just under halfway through LYAH and I have to say, it's not clicking at all. I can't put my finger on it but I feel like I'm not learning much.

Might try https://learnyouahaskell.github.io/ instead.

Learn You a Haskell (community version)

Repository: https://github.com/learnyouahaskell/learnyouahaskell.github.io