path: root/2022/captions/emacsconf-2022-workflows--org-workflows-for-developers--george-mauer--main.vtt

WEBVTT captioned by bhavin192

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Hello. Welcome to my first ever EmacsConf talk.

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This is really exciting for me.

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I've done lots of conferences,

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but rarely ones this technical and this nerdy.

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I also feel like

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I have something interesting to share.

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I come to Emacs relatively late in my career,

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only about six years ago,

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but I've been absolutely amazed

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at the innovation and commitment of the community

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to do things their own way.

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Oftentimes, these become things

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that are not readily available anywhere else.

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So, as I've been using Emacs

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(and Org mode specifically)

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a great deal in my day-to-day workflows,

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I've been leaning more and more into

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some of these tips and tricks.

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I find that there is almost every day

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that I discover some useful tweak

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that can make my development better.

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I want to share them with you now.

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[Future George]: Hey, hold on!

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Who are you?

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[Future George]: I'm you from the future!

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Oh, nice. How good.

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No, I'm you from, like, a month from now.

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Look, you know how these talks are pre-recorded,

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and you know how you've spent the last two years

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criticizing conference speakers

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for trying to do the same old thing

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and not creatively adapting

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to the online conference medium?

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Well, you are recording this back in November.

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I'm in December when everyone is watching this

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for the first time.

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That is something we can do now.

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[George]: Okay, so this is a gimmick.

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Cool! And I see you still haven't figured out

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how to remove backgrounds with OBS.

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[Future George]: Oh my god! It's such a pain,

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I have to get a plugin or something.

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So, yes, it's kind of a gimmick,

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but I also have a cool point.

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You know, how you just said

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that you discover something new every day?

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Well, your talk isn't that long,

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and I found a bunch of cool new workflow synths.

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[George]: Oh, okay, that makes sense.

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I'm starting a new job in the intervening time.

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[Future George]: Exactly!

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So, I have more stuff I want to add.

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[George]: Oh, and I bet that

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once we set the ground rules,

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the audience might have

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some of their own suggestions.

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That is a good idea.

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Okay, go away now.

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[Future George]: Fine, but

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aren't you gonna explain the dino?

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[George]: This is EmacsConf, dude.

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You think a dinosaur built out of

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boxes and old dishwasher parts

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is the weirdest background thing we'll see?

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[Both making dinosaur roaring sound: ROAAAAR!]

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Okay, bye now.

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Hey everyone, you heard the idea.

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This is going to be a thinly-veiled attempt

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to show you stuff about

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Emacs and Org mode, specifically,

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that I think is super cool and immediately useful

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while you're doing development.

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Let's define the scope of Org development workflow

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as something specific you do with Org mode

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that helps in certain common

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development related activities.

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Now, tie-dye me from the future said

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he's got some more ideas

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beyond what I'm presenting here.

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I'm sure many of you have ideas as well.

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So, we're going to share a collaborative document,

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and let's all as we're listening to this

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be talking, and chatting, and entering

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our own ideas and workflows,

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so that we can learn and improve together.

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And now with that, let's begin.

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I've got a ton of ground to cover,

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and I want to start by talking about note-taking.

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Shrink down! [transition]

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Note-taking is incredibly important.

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We can't keep all this stuff in our heads.

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So, for example, I find myself with

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the need to learn about the solid project.

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This right here is the solid project,

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and I want to play around with it.

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I am going to start by creating a note for it.

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Now, one of the things that I want to do

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is explore one of their tutorials.

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That's the site I just saw.

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I can go ahead and create a note for myself.

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Right, "Solid React Example",

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and maybe a set of stuff ending on there.

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I'm going to clone this project,

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which I've already done,

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and I can pull it up right here.

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So, I can pull it up right here,

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and I can now start to explore it.

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So, for example, this code base sounds…,

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it seems interesting.

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I'm going to want to

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store a link to this in my code.

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I'm going to run `org-store-link`,

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and I can come in here and say,

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let's explore structure. Local link,

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and here I'm going to put that right there.

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Now, at any given time I can come into this note

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and be thrown right into the structure.

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I want to go and now start investigating the code,

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but before doing that

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I'm going to take an extra step

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and customize the Org capture system.

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I'm going to create a playground node here,

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where I can do whatever.

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Now, what does this template do?

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Well, it's just going to create a new template.

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And whenever I hit the s key,

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it is going to go ahead and add a new heading

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to which I will enter,

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and it's going to grab a link

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to wherever I'm pointing at,

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and any highlighted code

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will also be inserted into a source block,

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and eventually, drop my cursor

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where I can work on it.

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So, we can grab our template,

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and the one thing I'm going to need to add it here

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is to say what file this goes to.

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I'm going to copy the name of this file,

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and put it right in there.

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I'm going to go ahead now run this template.

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Now, we can explore our code.

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For example, I can look in the server,

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and say, "Oh yeah, this slide looks interesting.

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Go ahead and capture that."

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There you see our template.

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You see, yeah, this is Next.js app,

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and you can see it got added right in here

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right next to my other code.

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So, that's interesting.

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I can always go ahead and click that link,

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and get thrown directly to where in the code I was.

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I'm kind of building up my own dashboard

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as I explore this project

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of interesting points within the project.

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One of the things I noticed here

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by looking at the file structure is that

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there is an area for certificates.

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That's a little unusual, so we'll make a note

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of that by again running `org-store-link`.

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This comes with certificates,

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so we'll put that there.

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One of the good standbys is,

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just to use our regular shell commands.

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So, we will go ahead and say,

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the default directory for this is our project.

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And we can go ahead and say,

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`cat certificates/localhost.key`,

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and then we'll output the first five lines of it,

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just to make sure it's a regular certificate.

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Now, notice this got broken up a little bit.

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This is due to Emacs auto formatting.

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We can come in here, and tell it to

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format it as code,

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which will be the same as this block right here.

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Now, there are other options available.

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If, for example, we don't want [it]

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to be a shell block,

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we wanted a Python block for some reason,

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we do `:wrap src python`, and execute that,

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and it's now wrapped as a Python block,

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but I like it as a shell.

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Let's, for example, go down into pages here

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and look at this document file.

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We're saying, "Okay. Well, this looks interesting

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maybe highlight that," and we'll go ahead

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and capture that template

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and say, grab all this code and paste it in here.

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Now, there is a bug at the moment,

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where if you highlight more than one lines of code,

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the link will not work, and that honestly

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might be something I look into fixing.

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One of the things that might be useful here

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would be to check out

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how this file has evolved over time.

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To do that, I'm going to use Magit.

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I'll pull up a log.

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Look, there's only a single change.

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I'm going to run a command

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called `orgit-store-link`,

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and now I can come in here and say,

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"It's only changed once."

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Go ahead and insert that link.

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Now, this file…

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the arguments here are kind of weird,

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and in fact, if I click this,

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it will actually go to the full log of that branch.

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However, we can fix that pretty easily.

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Grab the path of our file,

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and this right here is really just the arguments

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that are passed into the log command.

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So, here we go, we put that in there,

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and there we go. We get the full file history.

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Now, I want to actually build the program.

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So, "Build the app."

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Now, I could of course run it as a shell, right.

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`npm ci`. The problem with that is that

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Emacs is single-threaded. So, if I were to do that,

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the entire time while it was running,

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it would be locking out my Emacs.

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Additionally, I might not actually want

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all that scroll--`npm ci` produces a lot of it--

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actually in my document.

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So instead, what we could do is

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use an Emacs Lisp function,

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and it's called `async-shell-command`.

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And when you run something in async-shell-command,

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it's going to a comint buffer with a process

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attached to it, and run it in there.

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I will need to set the directory here first,

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and since, again, this is going to be

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opening up in a new buffer.

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I don't need to see that.

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I'm going to run it.

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And what's going to happen is

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this is actually not going to work.

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And it doesn't work,

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Not for any particular reason I can control.

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It's unfortunately that the repo is broken,

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but that is a totally valid

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result of our investigation.

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One of the things that I really love

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to do with Org mode is to actually use it for

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literate programming,

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because Org mode has a pretty capable

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code generation facility built into it.

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It's called tangling.

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So, if I go ahead and take my document...

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This is for a little Arduino project,

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where I was figuring out to spin things around

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using an old Roomba motor.

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I can go ahead and write a script like this,

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and then notice, I use the tangle variable

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that is just going to determine

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where that file gets written

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when we call the command `org-babel-tangle`.

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So, if I go ahead and run this,

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you can see down in the minibuffer,

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it's going to write to

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`/tmp/go-batsy-playground/go-batsy-playground.ino`.

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That's where this right here would write,

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and then I could run commands on it.

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Then I want to start being able to use this

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to build out a program.

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I'm going ahead and writing in prose

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and interspersing it with code.

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So, it's the inverse of code,

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in which you intersperse comments, [here]

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you write prose, and then you intersperse code

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where as needed.

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Tangle is implicitly defined up at the higher level

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in this property block right here,

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which I will talk about in a little bit.

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But if you want to see what properties

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are available at any given time,

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you can hit `org-babel-view-src-block-info`

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right there, and you can see that tangle is enabled.

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All of these blocks have the exact same tangle.

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If I run and see what it is, it's just going to

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write to this directory to `go-batsy.ino`.

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`org-babel-tangle` is going to go ahead

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and tangle all these source code blocks,

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and I can go ahead and look at my file

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and here it is.

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This is the full Arduino file

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that was generated from there.

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I start writing code here,

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and I'm basically doing it in a prose way.

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As I'm thinking about it,

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I write down what I'm going to do.

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Now these braces, we haven't seen these before.

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This is an aspect of Org called `noweb`,

00:13:52.680 --> 00:13:55.374
which again is not too much of a

00:13:55.374 --> 00:13:56.400
templating system too.

00:13:56.400 --> 00:13:58.960
But it does one thing, which is insert code,

00:13:58.960 --> 00:14:00.200
which turns out to be enough.

00:14:00.200 --> 00:14:03.640
So, this right here basically says,

00:14:03.640 --> 00:14:08.507
take that block with that exact name

00:14:08.507 --> 00:14:09.960
and just insert here.

00:14:09.960 --> 00:14:13.760
If you want to see exactly what a block expands to,

00:14:13.760 --> 00:14:15.160
you're going to come in here.

00:14:15.160 --> 00:14:18.320
You're going to run `org-babel-expand-src-block`,

00:14:18.320 --> 00:14:21.000
and there we go. That's what this block expands to.

00:14:21.000 --> 00:14:22.080
That's what all those places

00:14:22.080 --> 00:14:24.807
of this little bits and pieces expand to.

00:14:24.807 --> 00:14:26.120
So, that becomes really useful, and notice

00:14:28.120 --> 00:14:29.960
basically we just take these little blocks

00:14:29.960 --> 00:14:32.520
that are not going to be tangled directly

00:14:32.520 --> 00:14:33.920
but it will be in this other block.

00:14:33.920 --> 00:14:38.074
And we turn off their tangling.

00:14:38.074 --> 00:14:40.680
Now that you have some sort of tangling,

00:14:40.680 --> 00:14:42.880
you want to be able to interact with those files

00:14:42.880 --> 00:14:46.707
that are written to that directory.

00:14:46.707 --> 00:14:48.960
So, right here I have an area

00:14:48.960 --> 00:14:52.760
where I can do things like run a compiler.

00:14:52.760 --> 00:14:55.160
Now what does that compiler do?

00:14:55.160 --> 00:14:57.840
Well, this right here references

00:14:57.841 --> 00:15:01.874
a source code block that appears in another Org file.

00:15:01.874 --> 00:15:04.520
And I find that when doing these sort of things

00:15:04.520 --> 00:15:06.007
it can be useful to have a little

00:15:06.007 --> 00:15:08.000
utility Org directory.

00:15:08.000 --> 00:15:10.374
So, here it is, `org/ci.org`.

00:15:10.374 --> 00:15:11.640
This is just part of my repo.

00:15:11.640 --> 00:15:14.140
We open up, and here we go.

00:15:14.140 --> 00:15:15.200
I have a compile function.

00:15:15.200 --> 00:15:18.360
Basically, it's doing some stuff

00:15:18.360 --> 00:15:20.480
to clean up things correctly.

00:15:20.480 --> 00:15:23.520
But then using that same `async-shell-command`

00:15:23.520 --> 00:15:26.280
to open things up and a new buffer.

00:15:26.280 --> 00:15:28.674
In this case, named after

00:15:28.674 --> 00:15:31.200
whatever heading it was under.

00:15:31.200 --> 00:15:35.160
And then we're going to go ahead and inside of it

00:15:35.160 --> 00:15:39.874
run Arduino CLI command to compile,

00:15:39.874 --> 00:15:43.560
and pass that into `watchexec`.

00:15:43.560 --> 00:15:46.120
which is a little Rust program

00:15:46.120 --> 00:15:49.520
that watches inode[??] files for any changes,

00:15:49.520 --> 00:15:51.240
and when they detect them, we will run this.

00:15:51.240 --> 00:15:56.160
If I were to, for example, add a line here,

00:15:56.160 --> 00:15:59.360
and now run `org-babel-tangle`,

00:15:59.360 --> 00:16:02.400
you can see watchexec immediately

00:16:02.400 --> 00:16:04.480
picks it up and restarts it.

00:16:04.480 --> 00:16:07.474
Now it's kind of a pain to remember

00:16:07.475 --> 00:16:09.680
to run `org-babel-tangle` all the time.

00:16:09.680 --> 00:16:13.807
So, I can come here and click this button.

00:16:13.807 --> 00:16:17.040
It asks me to execute it there.

00:16:17.040 --> 00:16:18.280
And what does that do?

00:16:18.280 --> 00:16:23.280
Here you go. It's just a very simple hyperlink,

00:16:23.280 --> 00:16:25.600
but to the Elisp protocol.

00:16:25.600 --> 00:16:30.600
The Elisp protocol just adds a hook that says,

00:16:30.600 --> 00:16:35.107
whenever a document is saved, run `org-babel-tangle`.

00:16:35.107 --> 00:16:37.600
And now that I've run that, I can go ahead,

00:16:37.600 --> 00:16:39.307
come in here, and delete that.

00:16:39.307 --> 00:16:42.340
And look at that. It tangles automatically for me.

00:16:42.340 --> 00:16:45.040
Because I don't want to actually have this

00:16:45.040 --> 00:16:49.480
playground script tangle to my real file,

00:16:49.480 --> 00:16:51.440
I need this concept of

00:16:51.440 --> 00:16:52.760
some sort of workspace directory.

00:16:52.760 --> 00:16:54.880
And a workspace directory

00:16:54.880 --> 00:16:58.280
what I really want is a variable that is tied to

00:16:58.280 --> 00:17:02.674
where in my document hierarchy this appears.

00:17:02.674 --> 00:17:06.680
I want a dynamically scoped variable

00:17:06.680 --> 00:17:08.240
that's scoped to my document.

00:17:08.240 --> 00:17:12.560
And you can do that. For example, in this case,

00:17:12.560 --> 00:17:15.280
I have in my properties

00:17:15.280 --> 00:17:20.080
a key value declared `workspace-directory`,

00:17:20.080 --> 00:17:22.080
[it] goes into a temp directory.

00:17:22.080 --> 00:17:24.480
And here, by running `org-get-entry`

00:17:24.480 --> 00:17:25.800
starting at the current point,

00:17:25.800 --> 00:17:27.507
find `workspace-directory`

00:17:27.507 --> 00:17:28.760
with a second parameter 1.

00:17:28.760 --> 00:17:31.520
You can see down in the minibuffer,

00:17:31.520 --> 00:17:37.174
goes to `/tmp/go-batsy-playground/`.

00:17:37.174 --> 00:17:39.720
This right here is going to override

00:17:42.040 --> 00:17:44.307
the `workspace-directory` at the top level,

00:17:44.307 --> 00:17:47.607
which is dot. Dot means here.

00:17:47.607 --> 00:17:48.880
That's what makes sure

00:17:48.880 --> 00:17:50.680
that the rest of these tangle to

00:17:50.680 --> 00:17:54.560
that go-batsy file right relevant to here.

00:17:54.560 --> 00:17:55.740
And that does mean that we need

00:17:55.740 --> 00:17:58.207
a little bit more complex thing here.

00:17:58.207 --> 00:18:01.760
So, we're saying go ahead and `org-entry-get`

00:18:01.760 --> 00:18:04.800
the `workspace-directory`.

00:18:04.800 --> 00:18:06.807
If anyone hasn't seen this syntax,

00:18:06.807 --> 00:18:16.040
this dash arrow is from the dash.el library,

00:18:16.040 --> 00:18:19.240
which is basically a big library of all

00:18:19.240 --> 00:18:20.940
the utility functions that you wish

00:18:20.940 --> 00:18:22.880
Emacs Lisp had. They're well-named.

00:18:22.880 --> 00:18:24.480
I highly, highly recommend it.

00:18:24.480 --> 00:18:26.080
This is the threading operator.

00:18:26.080 --> 00:18:28.200
So, we're just basically taking it,

00:18:28.200 --> 00:18:29.760
getting the `workspace-directory`,

00:18:29.760 --> 00:18:32.307
if it happens to be dot, then we're just going to

00:18:32.307 --> 00:18:33.320
return the current directory,

00:18:33.320 --> 00:18:36.000
otherwise whatever directory said.

00:18:36.000 --> 00:18:39.240
And then I want to just take a moment

00:18:39.240 --> 00:18:41.280
and look at the rest of this structure.

00:18:41.280 --> 00:18:43.080
So, `workspace-directory` we talked about.

00:18:43.080 --> 00:18:46.774
`header-args` if you noticed, none of my

00:18:46.774 --> 00:18:48.707
code blocks for the most part

00:18:48.707 --> 00:18:50.840
have any header arguments.

00:18:50.840 --> 00:18:53.174
You can drop the `header-args` property,

00:18:53.174 --> 00:18:55.607
which is going to be header arguments

00:18:55.607 --> 00:18:57.840
that are added automatically

00:18:57.840 --> 00:19:03.407
to all source code blocks under this heading.

00:19:03.407 --> 00:19:05.407
`header-args+`. Well,

00:19:05.407 --> 00:19:06.540
sometimes you don't want to type…

00:19:06.540 --> 00:19:07.507
you have a bunch of args,

00:19:07.507 --> 00:19:08.240
you don't want to type them out

00:19:08.240 --> 00:19:09.440
in this one big line.

00:19:09.440 --> 00:19:11.040
So, you basically are adding a new header-arg

00:19:13.320 --> 00:19:15.407
to the existing list of header.

00:19:15.407 --> 00:19:18.160
And then you can have header-args that are specific

00:19:18.160 --> 00:19:20.440
to certain languages, like, for example,

00:19:20.440 --> 00:19:21.560
this `default-directory` var is going to be set

00:19:23.720 --> 00:19:25.200
for all Emacs Lisps.

00:19:25.200 --> 00:19:29.574
And for all Arduinos, evaluation will be disabled,

00:19:29.574 --> 00:19:32.440
and tangling will be automatically enabled.

00:19:32.440 --> 00:19:35.307
These are just some of the workflows that become

00:19:35.307 --> 00:19:38.320
useful when you're actually doing the coding.

00:19:38.320 --> 00:19:41.374
[Future George]: Oh, hello again!

00:19:41.374 --> 00:19:45.307
Me from the six months from now.

00:19:45.307 --> 00:19:49.107
[George]: Cool.

00:19:49.107 --> 00:19:51.000
[Future George]: The talk got over, people liked it,

00:19:51.000 --> 00:19:53.040
thought the pacing was all over the place.

00:19:53.040 --> 00:19:56.360
[George]: Yeah, I had to cut two thirds of it,

00:19:56.360 --> 00:19:59.800
going to be filling in those gaps in the Etherpad.

00:19:59.800 --> 00:20:03.520
[Future George]: And the editing was uneven, at best.

00:20:03.520 --> 00:20:05.507
[George]: I got way better at it

00:20:05.507 --> 00:20:06.680
as I worked on it, didn't I?

00:20:06.680 --> 00:20:09.960
Kdenlive is pretty cool.

00:20:09.960 --> 00:20:13.540
But yeah, I wanted to take a shot at

00:20:13.540 --> 00:20:16.040
something different, and I figured if anyone can

00:20:16.040 --> 00:20:17.760
appreciate trying something different,

00:20:17.760 --> 00:20:20.120
it's EmacsConf, right?

00:20:20.120 --> 00:20:21.520
I hope people found it useful.

00:20:21.520 --> 00:20:22.600
[Future George]: Yeah, some did.

00:20:22.600 --> 00:20:26.920
Oh, I should tell you about the coming Orca war.