Manipulate works and doesn't

[kaltsoplyn]

First off: Just found out about WLJS, Amazing work, thank you, will contribute!!

To my question, I gather that dynamic stuff like Manipulate are maybe not "first-class citizens" in WLJS, but here's an observation.
This works for me:

Manipulate[Plot[Sin[2 π a x] Cos[2 π b x], {x, 0, 1}], {{a, 1}, 0, 5, 1}, {{b, 1}, {1->"low", 2->"med", 3->"high"}}]

But this doesn't:

freqSelection = {1->"low", 2->"med", 3->"high"};
Manipulate[Plot[Sin[2 π a x] Cos[2 π b x], {x, 0, 1}], {{a, 1}, 0, 5, 1}, {{b, 1}, freqSelection}]

But this works again:

freqSelection = {1->"low", 2->"med", 3->"high"};
Manipulate[Plot[Sin[2 π a x] Cos[2 π b x], {x, 0, 1}], {{a, 1}, 0, 5, 1}, Evaluate[{{b, 1}, freqSelection}]]

Any idea why this happens?

[Wolfram Engine 14.3 | WLJS 2.8.7-x64]

P.S.: not to highjack my own thread, but is there a roadmap for quality-of-experience improvements in the frontend (e.g. merge/split/move cells, shortcut to evaluate cell & move to next [like, ctrl + enter or something], multi-select cells etc.)?

[JerryI]

Thanks, @kaltsoplyn !

I gather that dynamic stuff like Manipulate are maybe not "first-class citizens" in WLJS

Manipulate is an abstraction for WLJS's specific lower-level dynamics system (Offload technique, InputRange, and event system), which are kinda primary features of WLJS. It is originally started and grown with/from them. We added them far later to have compatibility with Mathematica. Our manipulate implementation uses diff-like approach to manipulated expressions, then translates them into more optimized version, where our low-level features are used (this is why JIT indicator is shown at the bottom), and deoptimizes it back if a new expression is "too different".

I guess, the problem is that Manipulate has HoldAll attribute, that matches specific patterns. We will check if we can fix that and let you know in this thread.

PS: You can avoid this if you pass your symbol using With...

[JerryI]

P.S.: not to highjack my own thread, but is there a roadmap for quality-of-experience improvements in the frontend (e.g. merge/split/move cells, shortcut to evaluate cell & move to next [like, ctrl + enter or something], multi-select cells etc.)?

Feel free to create a new one ;)
We have quite a lot of shortcuts actually including shift+enter. They are listed in overview section of the docs.

In general we follow what people mention in issues or discussions on Github (sometimes they vote) and then prioritize this or that feature. Last time it was somewhat about cells separators.

PS: I am not sure if it is worth to make a real roadmap, since the popularity and adoption of WLJS is quite low

PPS: you can move to the next cell directly with arrow keys

[kaltsoplyn]

Thanks for the response!

We have quite a lot of shortcuts actually including shift+enter. They are listed in overview section of the docs.

Oh yes, surely I'm using shift-enter, it's muscle memory from Mathematica.
What I'm saying is that it'd be nice if this (or another shortcut like ctrl + enter) automatically took you to the next cell so that your flow was not interrupted.

Right now it's:
shift - enter + down arrow + down arrow + down arrow + down arrow + down arrow + [start typing]
(some keystrokes seem unresponsive right after an evaluation)

What I would propose is the Mathematica-like:
ctrl - enter --> evaluates and positions the cursor below the output (or creates a new cell below the output and focuses on it)
start typing --> creates new cell (or starts writing into the newly created one)

As for the cell manipulation enhancements, I'll monitor what the other users say in the issues and maybe chime in on those or start a new one.

Again thank you all for this work!
It's probably expected that adoption is low, but this is really the absolute best way I've seen to date to bring mathematica into the hands of everyone (and with such a fresh take on the whole "notebook" experience!)

[JerryI]

Fixed (flow) in 2.8.8. And a new shortcut added Ctrl/Cmd+Enter
PS: Please make sure to clean cache (View -> Reload window) after an update

[kaltsoplyn]

@JerryI Wow, thanks, works like a charm!