path: root/2023/captions/emacsconf-2023-emacsen--the-emacsen-family-the-design-of-an-emacs-and-the-importance-of-lisp--fermin--main.vtt

WEBVTT captioned by sachac, checked by sachac

NOTE Introduction

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Hello, my name is Fermin.

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Today, I'm going to talk about the Emacsen family,

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the design of an Emacs, and the importance of Lisp.

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So we're going to talk about Lisp.

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I want to start from the end.

NOTE Why Lisp matters

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The first question I want to ask is

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why I think Lisp matters.

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When I'm talking about Lisp here,

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I'm talking about the idea of Lisp,

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so the family of languages that are Lisp.

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But given that there's no formal specification of Lisp,

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so the opinion might vary. I will expect that Lisp,

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most of the Lisp have these kind of features.

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The first one is homoiconic:

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the code is data, basically.

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They also have a REPL: read-eval-print loop.

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That is very powerful and can help in development.

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Also, I think a good Lisp

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should have a powerful macro system.

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I'm good with compile-time macros,

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but read-time is also interesting.

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There's a lot of Lisp that you can choose.

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There's the main three ones, of course,

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with Scheme, Common Lisp, and Clojure.

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Scheme by Guile, Common Lisp by Common Lisp,

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and Clojure by Clojure or ClojureScript.

NOTE Why Emacs Lisp was chosen

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So let's talk about Emacs Lisp.

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I didn't mention Emacs Lisp.

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I'm going to talk about why Emacs Lisp

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was chosen for an Emacs editor.

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We're going to explore this kind of design of the Emacs.

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And Emacs Lisp is the main language of it. Why?

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Given that there were a few alternatives at the time,

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why Emacs Lisp was chosen?

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So RMS, Richard Stallman, needed a Lisp,

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and there wasn't one available at the time.

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Keep in mind, this was the early 80s.

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Stallman was writing at that point the GCC, I think,

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and he was writing the core components

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of what is going to become GNU.

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He needed an editor. He wanted Lisp. He wanted Emacs.

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So he wrote Emacs Lisp. So at that time,

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the functionality was more important than "perfection."

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What I mean [by] "perfection" is: we programmers

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sometimes like to make everything good

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or very, very good when sometimes, indeed,

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it's more important that it works

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to do the task that it should.

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And it's not a bad language.

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It's not that bad. At that time, it was mostly nice.

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Today, it's good enough, I think.

NOTE Other "Emacsen"

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He wasn't the first one, the GNU Emacs,

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nor the only one, of course.

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There were others: Hemlock, Zmacs, and Climacs...

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Two of them, I think, were written in Common Lisp,

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and Zmacs was written in a Lisp from a Lisp machine,

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so it was an implementation of Emacs.

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Not GNU Emacs, but the original idea

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of Emacs for a Lisp machine.

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So Hemlock was written in Common Lisp,

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but it's no longer used and no longer developed,

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as far as I know. And Climacs, it was developed,

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but it was abandoned, I think.

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So three of them failed for different reasons.

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Zmacs was because of the Lisp machine market crash,

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and yeah, it also failed.

NOTE Why not Common Lisp?

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So Emacs got alone. And in the 90s, interesting to explore,

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some people suggest that why

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now that we have a standard Lisp, right,

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because Common Lisp was standardized in '94,

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why don't we change Emacs Lisp to Common Lisp?

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These are the other reasons I think are important,

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because that's why Stallman didn't choose Common Lisp.

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But I think the main one

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that I didn't write here

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is that Stallman wasn't a big fan of Common Lisp,

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and he was at the time the main developer

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and maintainer, of course, for Emacs.

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So he chose not to move to Common Lisp.

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But other reasons may be why...

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Because he had a late and painful standardization.

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Keep in mind, the first book that Guy Steele wrote

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was in 1984. The standardization finished in 19--

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sorry, in 1984 was the first book

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and the standardization finished in 1994.

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So, like, 10 years of difference from one to the other.

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10 years of a lot of talk, a lot of money,

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and a lot of pain probably.

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The Lisp usage declined in the 90s

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due to the AI winter.

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We all know about the Lisp machine market crash.

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And the failure of commercial Lisp machine was

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inevitable at that point.

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So all the potential Emacs friends died.

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And also a lot of Emacs Lisp was already available.

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Emacs was already an amateur utility.

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Unix won the war of the operating system, as we know,

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and Emacs Lisp was available in Unix,

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or in GNU/Linux, as we know,

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which is the most successful implementation of Unix.

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Sorry, BSD. Okay.

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So Emacs won by being the "better" alternative.

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I'm quoting "better" here because

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I think Emacs does have a better design

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and, well, it was the one that survived, right?

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Which is the more important thing for a software or,

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you know... So Emacs won by being free,

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also in price, which I think the Lisp machine wasn't.

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So that was also very good. It was included.

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It had, and it still has, of course,

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a nice collection of packages

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that improve the standard functionality.

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It was easy to extend because of the nature of Lisp.

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And it has a very good integration with GNU/Linux,

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of course. It was created to write it.

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It makes sense that it's very good

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for a system administration perspective.

NOTE Common Lisp is still not dead or is always dead

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But I think Common Lisp is not dead yet.

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Or some people say that it's always dead,

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so you cannot kill the something that is always dead.

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So I don't always code in C,

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but when I do, it's Lisp. I'm not a big fan of C

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for a lot of things, but yeah.

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Why I think Common Lisp is still relevant

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and can be used for all kind of application,

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both commercially and non-commercially.

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The first one is the main implementation

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of Common Lisp, which is called SBCL, which is awesome.

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It's fast. It's a very good extension.

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Basically, it's the reference one today.

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The namespaces of common Lisp,

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I really like the implementation.

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Some people don't like it. It's a matter of taste.

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But I think it's really good.

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I have a timeless standard. So it was standardized

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in the 90s, as I said.

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And it doesn't really need a new standard.

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Some people say it does need, but I don't think so.

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Also it does have macro readers,

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which I think is a very nice feature of Common Lisp

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that other Lisp doesn't seem to have,

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or a lot of them don't: in my mind, Emacs Lisp and Clojure.

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Also, it's image-based development,

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which is also quite unique to Common Lisp.

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I don't know all the Lisp that does have this.

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Basically, you develop a REPL

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and then you dump the entire REPL into an image.

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Java would be like a core dump.

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And you create an executable.

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Which at the time, I guess in the 90s,

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was a huge one, right?

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Because you have the entire language, and the REPL,

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and the code. But today are like 20 MB,

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which in today's standard is nothing.

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There's pictures in your phone larger than 20 MB.

NOTE Lem is a nice Emacsen implementation

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So there's a new Emacs in town--well, Emacs, not Emacs,

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Which is Lem. I think it's a very good Emacs implementation.

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What I mean by "Emacs" here is not a clone of GNU Emacs,

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but an Emacs-inspired editor with similar characteristics,

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and written in a Lisp,

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which is why I said that Lisp was very important.

NOTE Why not just use GNU Emacs?

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So first, I'm going to address the elephant in the room,

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and the question that maybe most

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of you are now thinking.

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Why not just use GNU Emacs? It's the project.

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It's the main one, right? Why choose another one?

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So Lem is relatively new, 2018.

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And it can explore different ideas.

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It was developed by Sasaki-san.

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Basically, it was mostly a one-month project,

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but we are getting there. I'm not the maintainer.

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I'm a developer of Lem. So given that it's

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relatively new, it can explore different ideas.

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You're not bound to a community or backwards compatibility.

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You can explore different ideas,

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and I think that's always nice.

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Having multiple options creates competition,

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which benefits the community. So Emacs and Vim,

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the competition between the two

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always create nice packages like evil or, you know...

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It's really good to have some kind of a competition,

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healthy competition.

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And it doesn't share any code base with GNU Emacs.

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I want to clarify this because some people think that

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Lem is kind of a, you know, Spacemacs or Doom.

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No, it doesn't share any code.

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It has zero Emacs. So that's it.

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Getting this out of the way.

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Why I think Lem is interesting.

NOTE Why Lem

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I'm going to show why Lem.

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Why? You can try Lem, and maybe you like it.

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First thing, these are the features

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that I really like from it.

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Can be different from person to person,

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but I think these are the main ideas

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it brings to the table and are really interesting.

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I want to say that Lem is not a research project.

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It's not like some people did that

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and it's still in development. No, no.

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This is a usable product that can be used

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to [do] day-to-day programming

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in a very good experience.

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This is not like--I want to clarify this

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because some people bring some exploratory projects.

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This is not that one. This is finished.

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Well, finished in the way that you can use it.

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It's not, you know, have everything in place.

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So let's continue.

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It's written 100% in Common Lisp.

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I say this because Emacs is not

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100% in Emacs Lisp.

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You have to modify the C code,

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I think, well, if you... You don't have to,

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but if you want to change the internals, you do.

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I think that given that Lem does not care

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about the implementation of the language itself--

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so for example, Lem doesn't have to deal with

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how Common Lisp works, it just used the language, right?

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It's on top of the language.

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You can say that. Emacs Lisp is Emacs and Emacs Lisp,

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so you have to, you have both in the same place,

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which is, well, it's a double-edged sword, right?

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Then you have the both--similar to Emacs--

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you have ncurses and SDL2 frontends.

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One is terminal-based and the other is graphical

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using the SDL2 library,

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which you can do a lot of crazy things.

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Of course, it's meant to program games and stuff,

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but Lem uses, and it works fairly well.

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You can program games if you want.

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Not that you need to or anything, but we have Tetris.

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So there's that.

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Also, separate front-end interface.

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So like I said, you have two, but you can create more.

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In the past, had an electron one,

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but it got abandoned for obvious reasons, I think. Sorry.

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This idea is taken from Neovim that had a lot of frontends.

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In fact, we don't have that many,

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but not that many people we have two.

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That works fairly well.

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We have superb development experience thanks to SLIME.

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So we have Micro,

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which is a SLIME version for Lem, basically.

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SLIME is awesome and Micro is also awesome.

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We have a very strong development experience

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that we don't have for a Lisp,

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which I think is very important.

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If you want someone to develop packages or to use your tool,

00:13:20.320 --> 00:13:22.719
your Emacs at least,

00:13:22.720 --> 00:13:28.759
you need to have a very good development experience,

00:13:28.760 --> 00:13:34.039
which enhance the extensions for the editor.

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So we have also Vim-like integration.

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This for me was mostly mandatory

00:13:39.400 --> 00:13:44.439
because I'm an evil-mode user, and I think it's really good.

00:13:44.440 --> 00:13:49.479
Because evil-mode is very good and the VMode,

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which it's called, even though it's more like Vim mode,

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it's called VMode. It's written by

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Fukamachi-san and it's really good.

00:13:59.160 --> 00:14:01.959
So yeah, that's the thing that I think Lem brings to

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the table and that's really interesting.

NOTE Similarities and differences

00:14:03.080 --> 00:14:10.519
So I'm going to do a small demo of Lem, a Emacs example.

00:14:10.520 --> 00:14:11.679
First, the similarities,

00:14:11.680 --> 00:14:14.119
the nomenclature is very similar: modes, buffers,

00:14:14.120 --> 00:14:17.439
commands... The commands are very similar in nature.

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It was written with GNU Emacs in mind

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to mimic a lot of things.

00:14:24.360 --> 00:14:29.079
I think GNU Emacs is the best Emacs implementation

00:14:29.080 --> 00:14:33.719
in that way. So why not just take what is working, right?

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I have similar command,

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but flexible to add other default ones.

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It's not like Emacs that you have Emacs commands.

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Lem has Emacs command by default,

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but you can easily change that

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with other default ones, right?

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It's like, you can think of it like a major mode, right?

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Well, more like a global mode,

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sorry. That's a global mode of Emacs commands,

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or something like that.

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In general, the feeling is really close.

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So you will tell that it's really close to how both work,

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similar commands, and that shows.

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Differences, Common Lisp is not Emacs Lisp,

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it's similar in the surface.

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So it uses `defun`, you know, have parentheses

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and yada, yada, but it's not the same language, really,

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and sometimes you will find

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that the differences are substantial.

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The internals are completely different,

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of course, nothing, well, completely.

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They have a buffer implementation and other things,

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but in general, yeah, aside from that,

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it's completely different.

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And it's true that GNU Emacs

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has a better documentation tutorial.

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So GNU Emacs for me, I think it's

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one of the best-documented software ever.

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We're trying to go there, but we're still not there.

NOTE Demo

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Let's do the demo. So to open Lem, you compile it,

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and then you have it available,

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and you open Lem. As you can see,

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we have the temporary buffer. On the top left is the mode--

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not mode,

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the beam, insert, normal, visual. This is the V mode, right?

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In the top right corner, we have fundamental,

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which is the major mode, then paredit,

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which is like the minor mode, but you know,

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this is like the paredit for Emacs.

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In the top left buffer,

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you have the current buffer.

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So let's open the... Emacs, we all know how to do this.

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This is a command, like explore this command,

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like `open-init-file`. This opens the init file,

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which is in this directory, in `~/.lem/init.lisp`.

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As you can see, this is very similar, right?

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You define a command, which is not interactive,

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and then you get the buffer, right?

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This is a... So my personal command...

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Let's go to the one that I just opened. Init file, right?

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So this is a command that I did,

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which is `find-file`.

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This is very similar to [??], but just `find-file`.

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As you can see, very similar.

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This is the way that you program in Lem.

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This is the major mode, which is Lisp,

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that we're seeing at the top, right?

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And we can connect if we `slime-self-connect`.

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This is the prompt. This is the REPL.

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So if we... Keep in mind that this is Common Lisp,

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so this has different things.

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So we have to go to the Lem package,

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which is very important. This has namespaces, right?

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It's not the same. And we can say, okay,

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`current-buffer`. We get the buffer.

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We can explore everything that is in it, right?

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We have all this stuff. This is... If you're familiar

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with SLIME or Sly, this is it.

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It's just that we can say, buffer, I think it's `buffer-name`.

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Yes. And we can take this,

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and then we'll give you the name.

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So as you can see, the development experience

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is really powerful. We can also `lisp-scratch`,

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which transform... basically apply

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the major mode of Lisp to the temporary buffer.

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This is very similar to Emacs.

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Let's go back to the theme. I think that's it.

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Thank you all very much for listening to me.

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I think I point out

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the Emacsen family is really interesting.

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Lisp is really good, and GNU Emacs is really good,

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and I think Lem is also pretty awesome.

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So thank you all very much.

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I'll be answering the question now. And happy hacking.