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`,
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which again is not too much of a
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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.
