📺 Show stdout and stderr in notebook

[fonsp]

For backwards-compatibility with software written in the 70s 😵‍💫 code that still needs to make the switch to Julia's awesome Logging system!

I tried to use visual design to address the reasons that we originally had for not supporting stdout in Pluto:

• In the Julia REPL and Jupyter, It can be hard/impossible to understand the difference between something being returned and something being displayed as text. In a descriptive dataflow system, this difference is important!
• Motivate users to return values (much nicer display system), and to split large code into smaller cells.
• Motivate users to use Logging for logging, not 🖨 printing unstructured text to magic buffer.
• Stdin/stdout is often presented as a "basic feature" of a language, but I disagree! I see it as a niche feature for inter-process communication and super-optimized IO, not something we should teach to beginners. 🤕

Anyway, it turned out to be more confusing/frustrating to silently hide stdout, so here we go! A boring old terminal

Some common functions that didn't work before!

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You like ASCII art? Then you will love real art!

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Oooh is this hacking!?

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Schermopname.2022-02-25.om.23.56.18.mov

Help what is this green stuff!

xoxo
~ @fonsp

[github-actions]

Try this Pull Request!

Open Julia and type:

julia> import Pkg
julia> Pkg.activate(temp=true)
julia> Pkg.add(url="https://github.com/fonsp/Pluto.jl", rev="stdout-to-crt")
julia> using Pluto

[icweaver]

"But can you make it so the printy thing shows up in the notebook?"

Fons:

But seriously though, this is magnificent

[fonsp]

Tests were failing because of race conditions in main, I addressed these in main: 8f088f7...a13644e

[diegozea]

Hi! Small question: Will it be a way to hide stdout/stderr without hiding the returned value? In Jupyter is sometimes annoying (and slow) to run processes that fill stdout with a massive amount of text; would that be also a problem with Pluto in the future? Cheers,

[fonsp]

Yes, in the ... button next to cell, you have the option to hide logs (this PR turns stdout into a special log). But please try it out and let us know if this helps! Maybe we should also set a maximum size on captured stdout

[gdalle]

This is brilliant! Thanks a lot

[fonsp]

Fix #890