Incorrect example for ⎕IO=1 on page /SystemFunctions.html

[AleBeda]

This example does not look correct. The second result should be 1 2 3 4. The reason is that the assignment of ⎕IO should precede ⍳4.

⍳4
⎕IO←0
⍳4
⎕IO←1
0 1 2 3
0 1 2 3

[NaincyKumariKnoldus]

Hey @AleBeda I would love to do this. Can I?

[AleBeda]

@NaincyKumariKnoldus, the repository is not mine. It's up to @xpqz to decide. He probably won't mind if you send him a PR.

[NaincyKumariKnoldus]

okay @AleBeda sure I am doing it.

[NaincyKumariKnoldus]

Hey @xpqz and @AleBeda I have raised PR for this. Please review this.
Thanks!

[xpqz]

Hi @NaincyKumariKnoldus annd @AleBeda -- and thanks for taking the time.

It's in fact the first result that's wrong; I was relying on ⎕IO being defaulted to 1 when you open a new session in a notebook, but the build system that makes the book has an IO-setting that 'spills over' from an earlier chapter. The last ⎕IO←1 in the section you highlight is simply to return to the default. I'll make it clearer.

For future reference, the HTML pages are auto-generated from the Jupyter notebooks that make up the source for the book; thus any PRs would need to target those, as any changes to the HTML pages will get overwritten next time I run jupyter-book build. See https://jupyterbook.org/basics/build.html for details on how that works.

[NaincyKumariKnoldus]

Okay! @xpqz You mean to say I have to change first result not second result. Right?

[xpqz]

That was my intention, but it works doing it like so, which should be immune to this problem:

⍳4 ⊣ ⎕IO←0
⍳4 ⊣ ⎕IO←1

[NaincyKumariKnoldus]

okay I am changing first result. Correct?

[xpqz]

I've fixed it already this time. But as I said, your PR would have needed to target the notebook itself

Fixed in 142e6af

[NaincyKumariKnoldus]

Means ......I havent understand.

[xpqz]

So assuming you're not familiar with jupyter and jupyter-book....the book is built from jupyter notebooks and the Dyalog jupyter kernel. The website's html is automatically generated, and need never be modified manually.

The notebook in question is this:

https://github.com/xpqz/cultivations/blob/main/contents/SystemFunctions.ipynb

Any changes to the book's content text, code examples etc always go in the notebook files (contents/*.ipynb). The _build/html/*.html files are build artefacts only -- they're generated by the jupyter-book build contents command.

Whilst the notebooks themselves are basically just a bunch of json, they're not intended to be edited directly. Instead, in order to make changes to the notebooks you need the following bits and bobs installed:

1. Jupyter itself (https://jupyter.org/)
2. the Dyalog jupyter kernel (https://github.com/Dyalog/dyalog-jupyter-kernel)
3. the jupyter-book authoring system (https://jupyterbook.org)

With that in place, you can edit directly in a web browser, crucially including executing APL code in place.

Your PR changes the build artefacts, not the source. Instead, had you changed the notebook source, the build process would have executed the APL snippet, and included the (correct) output into the generated html.

Don't let this put you off: you spotted a problem, reported it, and it got fixed. Play around a bit with the jupyterbook system; it's a super-cool tool chain to do this kind of thing with.