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lakesare

Re:Show HN: WriteRush – The writing app that feels like a game on Tuesday September 16, 2025 @04:27PM (#45267515)
Loving the sepia theme, and in general fells really pleasant to me (something I did lack in other writing software). I think I will try it for my next project :)

Show HN: Meresei – Calendar for Non-24 (Sleep-Wake Disorder)

https://meresei.com

I have non-24-hour sleep disorder with a 25-hour cycle, and used to draw these calendars manually in Excel to track my shifting sleep schedule. Finally automated it.Green cells show when you're awake. You can click any cell to toggle it (useful for marking unavailable times when sharing with others). The "padding hours" feature helps set buffer zones around sleep/wake times.Been using this...

( Read More... | no comments | 2 points | on HN )
Re: on Saturday September 23, 2023 @04:01PM (#37626910)
Thanks for the link. I've been reading Leslie Lamport's TLA works this year coincidentally, but never stumbled upon this one. His structured proofs would turn into a paperproof-style tree if he turned his 3.1.1.1. numbers into a tree, it's pretty close to paperproof conceptually.

I don't know of any software that allows for manual writing of such proofs yet, I'm drawing proof trees on paper at the moment. I would like paperproof to allow for this eventually. We want to enable ml-generation of tactics with ReProver, which will require the interface for the manual creation of goals and hypotheses. Hopefully after that it will be more clear what fully-manually-written proof interface could look like.

Re: on Thursday September 21, 2023 @08:35PM (#37606407)
Reminds me of characteristica universalis
Re: on Thursday September 21, 2023 @07:02PM (#37605632)
I love "Lean" actually, have you noticed ∃∀. Googling Lean concepts does primarily return the codeine syrup links though yes.
Re: on Thursday September 21, 2023 @06:56PM (#37605574)
That's correct, in fact we would have a DAG if we displayed all possible arrows, but we conceal it to make the UI easier to interact with for the user. Hypotheses (green nodes) form many little trees, and goals (red trees) form a single tree. These must be trees, and not lattices, because that's just how Lean and Coq tactics work. However, tactics make use of hypotheses, and these can be displayed as arrows that connect hypotheses and goals, making it, in this sense, a DAG (here is an example, I moved the nodes a bit to make the arrows obvious https://github.com/Paper-Proof/paperproof/issues/9#issuecomm...). Concludia looks interesting, does it support first-order logic/ORs?
Re: on Thursday September 21, 2023 @06:18PM (#37605214)
It isn't necessary to know theory for these visualisations to be useful, both Traf and Paperproof (and sequence calculus trees!) should, ideally, just reflect what's already happening in your mental image while you're writing a Lean/Coq/on-paper mathematical proof. But I agree it warrants a tutorial/explanation, got to write it. I think it might be particularly unclear what's happening if you're just looking at the full tree of the already-proved-theorem. As we're writing the proof, hypothesis nodes (green, what we have) move down; and goal nodes (red, what we want to have) move up. So it kind of goes from both sides to the center, and you should read it "from both sides to the center", takes getting used to. Here is a video of what's happening in Paperproof as we're writing the proof e.g.: https://www.youtube.com/watch?v=0dVj4ITAF1o.
Re: on Wednesday September 20, 2023 @07:48AM (#37583023)
This is my overview of proof visualisation tools among all modern proof assistants.

If you're aware of any tools I might have missed, please @ me in the comments. I aimed to cover every one I could find.

Re: on Tuesday September 19, 2023 @07:22PM (#37578448)
A blog post where I catalog all Lean [proof assistant] books that exist in nature, share my opinion on them, and suggest learning paths for Lean novices.
Re:Demystifying tables (cells inside; borders outside) on Wednesday September 14, 2022 @07:46AM (#32835817)
It does violate the perfect "Cartesian coordinates" normalization I described earlier, however I consider this is a permissible step up over the full normalization, because, while cutting down repetition (entirely), it still suggests a zero-ambiguity way to read off the values from the header cells.
Re:Demystifying tables (cells inside; borders outside) on Wednesday September 14, 2022 @07:18AM (#32835610)
Hah, it basically goes into denormalisation!

This certainly looks prettier than the initially shown full-fledged table structure, however I'm having more trouble reading it - it makes me slightly uncertain what text belongs to what row, and whether I properly track the row lines with my eyesight.

Re:Demystifying tables (cells inside; borders outside) on Wednesday September 14, 2022 @06:42AM (#32835350)
Sounds interesting, please link me to those guidelines if you stumble upon them!
Re:The Myth of the Good Practice on Wednesday September 14, 2022 @05:35AM (#32834954)
No gods no masters no best practices
Re:Show HN: I made a minimalist spaced repetition tool on Saturday July 25, 2020 @07:57AM (#23948541)
Have you tried the open-source SRS https://www.memcode.com folks? With images & formatting & SM2 spaced-repetition algorithm too.
Re:Open-source spaced-repetition site for developers on Wednesday April 22, 2020 @07:32AM (#22944447)
Hi! I'm the author, I'd love to introduce Memcode.

Memcode is an open-source flashcards site, created with STEM students/developers in mind.

I created it because other spaced-repetition sites I've tried didn't include essential (for me) functionality, such as: - navigation via shortcuts, - code formatting, formulas, images in flashcards, - and easy fast course creation, with course creators as first-class citizens in mind.

Questions are welcome!

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