5 HN users recommended this demo4 months2014–2021score 4
Years with an HN recommendation, 2007–2026
Recommended as a charming, from-zero introduction to APL and a window into early interactive computing.
A 1975 live demonstration of the APL language by Imperial College professor Bob Spence, showing a REPL on a modified typewriter terminal and APL's appeal to non-programmers.
“I think this is a good youtube video for someone starting from zero” (HN, 2017)
APL without native fonts isn't fun at all. This is real fibonacci in APL: [link] [link] This is a nice introduction into APL: [this video] And this is how APL is applied in the right way: [link]
I think this is a good youtube video for someone starting from zero: [this video] An issue is how to enter the symbols. The way I do it is I created some input methods for Mac and Windows which use at-signs followed by the APL community name for the symbol: @times × @grade ⍋ @reverse ⌽ @domino ⌹ [link]
There is something so charming about the attached video [0]. It's very reminiscent of the original APL demonstration [1] from 1975. I love it! 0. [link] 1. [this video]
I think the key to understanding APL is realizing that it’s not built for Programmers; it’s built for Mathematicians. Here’s a fine half-hour introduction to APL in action: [this video] 1:00-2:00 is the motivation for APL—or any DSL—in a nutshell. (“conversational computing”, “users who are [not] professional programmers”) Or, if you’re happy to sit back and see math magic happen: [link] For all its mechanical advances over the last 40 years, it’s shocking how far our technology has regressed philosophically.
Half-hour intro showing APL's motivation for non-programmer users.
Thanks for sharing. I worked on the UIUC campus for some time right by the greenhouses where they experimented with cultivars of corn and other grasses, always funny to see giant 8 foot tall plants lit with sodium lamps through the winter. As for APL, I haven't really got past an orientation in the language but it's held a total mystique to me since seeing this video circa 1975 [0] walking through the language with a Selectric teletype acting as a REPL, totally flipped my understanding of computer history, I assumed it was all punchcard programming back in the old black and white days xD (I am born 1990 for reference, trying to catch up with what happened before me) [0] (30min) [this video]
REPL on a Selectric teletype upended view of computer history.
I enjoyed learning how they added a rotating ball to that typewriter and hooked it up to some kind of mainframe for the first APL implementation I think. [this video]
Shows early APL on a modified typewriter terminal.
You have posted an amazing and comprehensive comment. > If you look at the symbol, it looks like a rectangle with a division symbol inside. If you skip exactly 20 minutes into this video it IS EXACTLY a rectangle with a division symbol inside: [this video] I don't know whether to think "thank goodness for unicode" or "unicode is an enabler of problematic practices" :)
I love it I'm imagining a sixty year old dude, revered by all around him, who spend the last forty honing his fixed-form Fortran skills. Young engineers gather around him just to marvel at this masterpiece: [this video]
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