Lisp in Web-Based Applications (2001)
57 points - last Monday at 11:51 AM
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Here you will find some screenshots of some of today's web applications built in CL: http://lisp-screenshots.org/ and here an opinionated tutorial: https://web-apps-in-lisp.github.io/ One example: ScreenShotBot https://screenshotbot.io/ a successful open-source product and company. It now replaced Facebook's automatic screenshot testing tool (source: their blog). So, web apps in Lisp are possible -with a right amount of learning time and elbow grease.
The incremental development and interactive top-level are still precious and unmatched.
It was one of those things where 1-3 programmers, working with the right tools and thinking, could out-perform all competitors, no matter how much resources competitors threw at the problems. (I can't take credit for the initial architecture and implementation: that was all someone else.)
The system actually outlived Viaweb by decades, and I suspect still uses Scheme for a lot, especially for the necessarily complex backend.
(Half the problem for Scheme uptake was that most students only saw it school, as presented by a CS professor in an intro class, and then they did annoying homework, so they hoped never to use it again. They should've seen what we did with it, making it fly in ways that a CS professor wouldn't in first-year classes, compared to how it would've been done in other languages at the time.)
> One way we used macros was to generate Html. There is a very natural fit between macros and Html, because Html is a prefix notation like Lisp, and Html is recursive like Lisp. So we had macro calls within macro calls, generating the most complicated Html, and it was all still very manageable.
We just used lists and functions for HTML. And often with quasiquote, when we wanted to splice "dynamic" bits into a substantial chunk of "static".
I didn't try to use macros for HTML until a decade after this talk. I liked the simple DSL, and leaning on buffered I/O ports and string ports, but nobody else seemed to like it as much as I did (maybe because they didn't have a prolific colleague doing 10x code-writing in a rather more delicate way of generating HTML):
https://www.neilvandyke.org/racket/html-template/
(Don't look at the code, though. I wrote it before Racket got submodules, which are great if you have a strict, non-CL-ish module system and syntax extension mechanism that otherwise make some things much harder than in CL. I have a TODO note in there to refactor it with submodules, but I had to redirect my time towards other languages, for reasons having nothing to do with language merit.)