flow-typed VS Scrawl-canvas

I'm very curious, which "Redux code" are you referring to here?

I don't think the `redux` core lib ever shipped any Flow types itself. Looking at the FlowTyped repo, I see community typedefs at https://github.com/flow-typed/flow-typed/tree/master/definit... , and the Git history suggests those were indeed written by community members.

(of course on the flip side, _I_ didn't even start learning TS myself until 2019, and goodness knows _that_ has been a lot of trial and error over time :) )

As for configurability of whether casts should error, in my experience with flow it's paradoxically riskier to rely on a type nag when refactoring an unknown "offending" type casts. I've ran into cases where upgrading flow raised a cast issue, it got "fixed" it in a way that made the type system happy, but inadvertently broke tests because falsy values are tricky like that. Here's an example where a type nag showed up for someone refactoring, they did what they thought was reasonable to silence it, and proceeded to accidentally break the entire tool (slipping through tests and code review, to boot). This happened in the flow-typed tool of all places.

The process of supporting Flow users is extremely similar to that of TypeScript. Instead of adding the definition file to "types" in package.json, make a .js.flow file alongside every .js file that is being exported (for example, if you export lib/index.js, make sure to create lib/index.js.flow with the definitions). See the docs on how to create such a definition. If you want to support Flow yourself, don't publish to flow-typed; it's mainly meant for community members to create their own types for third-party packages and publish them there.

> working with glyphs and iterating them in reverse for RTL is brain-breaking. And line wrapping gets really complicated. It's also the most obscure because nobody has written down everything you need to know in one place

I can confirm this. I've been working on a (much simpler!) text layout engine for my canvas library over the past couple of months and the amount of complexity associated with just stamping some glyphs onto a canvas has left me screaming at my laptop on an almost daily basis. Getting a decent underline was a proud moment!

Question: did you ever find out what algorithm the various browsers are using to calculate how many words can fit on a given line? I'm almost there, except words will occasionally jump between lines when I scale the text. Really annoying!

The PR's still a work in progress, but I've got all the functionality I want in there (shaping lines to fit in non-rectangular containers, styling text, text along a non-straight line, dynamic updates, etc). Just need to test and document it all now ... https://github.com/KaliedaRik/Scrawl-canvas/pull/75

I've got myself organised and prepared a List Of Things To Do[1] to make my 2D Javascript library even better than it already is. Given that I've been working on the library for over 10 years now, and have never before set out such a list, I call this Progress!

[1] https://github.com/KaliedaRik/Scrawl-canvas/discussions/cate...

'Kay, I don't know if this anywhere close to what the OP wants, but this sort of live browser tab manipulation is possible to do using a mix of a a canvas element and the browser's Screen Capture API[1] (plus my JS canvas library, once I merge and publish the changes into its next release[2]).

This solution[3] shows the modified browser tab in a separate browser tab. I've got no idea whether it's possible to do the same sort of trick in the same tab (but probably not). I also have no idea how secure the Screen Capture API is - I'd get very nervous about doing this sort of thing when looking at my bank's online portal!

[1] https://developer.mozilla.org/en-US/docs/Web/API/Screen_Capt...

[2] https://github.com/KaliedaRik/Scrawl-canvas/pull/57

[3] Youtube video of the effect: https://www.youtube.com/watch?v=hCi6LmKMAo0

My canvas library's README[1] has a video embedded in it. FWIW I'm not convinced it adds anything to the library's sales pitch.

[1] https://github.com/KaliedaRik/Scrawl-canvas

> And I’m just mentioning some of the unfixable problems with this approach

I agree that using a canvas instead of leveraging existing accessibility supplied by HTML/CSS/JS and the DOM is an accessibility nightmare.

However, I disagree that canvas accessibility issues are "unfixable". Difficult? Yes. But not unfixable. In my view, the element works best in partnership with its wider environment (HTML/CSS/JS and the DOM), not as a replacement for it. With that in mind, we can start to tackle the accessibility issues you raise - fonts, links, interactions, etc.[1][2]

I have an ambition to one day become intelligent enough to understand/code in Rust, and I'm really glad to see that people are thinking about accessibility as a fundamental part of UIs being developed in Rust.

[1] - Which is what my JS 2d canvas library tries to do: https://scrawl-v8.rikweb.org.uk/

[2] - My thoughts on accessibility, and how I try to fix them using my library: https://scrawl-v8.rikweb.org.uk/learn/eleventh-lesson/

If, however, your company is set on this course, I very strongly suggest you use a canvas library - if only for the MVP. Here's my canvas library (spam alert!) ... even if you don't use it in your product, the library might help give you some ideas on how to overcome some of the responsive, interactive and accessibility issues you'll be facing.

Scrawl-canvas - example and another example (links to code at bottom of each page)

My personal experience as a library developer, who has written my library in JS, not TS ...

TS is an excellent choice for a lib dev starting a new project today. I can see the advantages of using TS for the library code - in particular for a library that gets popular and welcomes contributions from other developers. However TS is a nightmare for someone like me who: 1. started writing the library 9 years ago; 2. has let the library get "quite" big; and 3. has only learned to use TS in the past year (for the day job) and is nowhere near to becoming a types expert.

I've had experience of people suggesting I rewrite the library in TS. Sometimes those suggestions have been quite 'evangelical' in their tone. As an (essentially) solo developer I just don't have the time, capacity or willingness to do that work - however much the end results might please others.

I also understand that having type definitions file for the library's interface is, nowadays, a critical factor if the lib dev wants others to use the library in their projects. But writing a .d.ts file for a large, mature repo to at least help those potential users can quickly turn into a World of Hurt. I know this because I've done that work[1] and I never want to do it again.

As much as I know that TS is a Force for Good in the JS coding world, there are days when I detest it!

[1] - link to the Scrawl-canvas .d.ts file on GitHub - https://github.com/KaliedaRik/Scrawl-canvas/blob/master/sour...