Hi Viktor, really this is a quite different q than the thread talking about a learner's experience. You're writing deeply-technical detail not at all aimed at beginners. There's a very broad range of reasons and prior knowledge for readers of Library docos. But I disagree with this:
The beginner to intermediate users will be using the library and existing instances for some time before they start to write their own instances.
I'll want to write an instance of Foldable as soon as I've declared my datatype, won't I? Or do you expect me to be folding only over Lists? Speaking for myself, if I want to understand a function, I look first at its type then its source definition. The Laws for the particular Foldable example I don't understand at all. I'd say: hide those Laws as far away as possible. In fact, since the blasted FTP re-organisation of that library, I've more or less given up. Too hard/too abstract/too much Category Theory. What's an `Endo`? Thank you for your efforts to document. I expect there's someone you're helping. Not me. I don't think it's that the style "sucks". This style and content is enough for me: https://www.haskell.org/hugs/pages/libraries/base/Data-Foldable.html
Of course the conjectured users who might most benefit from not being intimidated by being exposed to laws before they're ready to understand them might not be present on this forum...
* The last time I went to look at the laws it took me a couple minutes to *>* find them. I use them to write instances. Pretty important, IMO.
I've gone well beyond the point of being intimidated by Category Theorists. I find they're doing a splendid job of putting people off getting to love Haskell as I used to. If you want to tell me off for speaking out of turn, go ahead. (But this forum is the cafe, perhaps this particular discussion should be on glasgow-haskell-users?) AntC On Thu, Sep 16, 2021 at 06:51:42PM -0400, David Feuer wrote: * I agree the laws are important to document, I just don't think they belong at the top of the module. The beginner to intermediate users will be using the library and existing instances for some time before they start to write their own instances. If more modules adopt something like the style of the new Data.Foldable, experienced users will know to look for the laws at the end, if not still present at the top of the module. Of course perhaps the community would prefer the original Laws first format, I'm fine with that emerging as the consensus. Perhaps worthy of a separate thread (made it so). Of course the conjectured users who might most benefit from not being intimidated by being exposed to laws before they're ready to understand them might not be present on this forum... --