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APL demonstration 1975

Imperial College London

244K subscribers • 1 video on Hallway

YouTube
  • Recommended by 8 people: 5 on Hacker News, 2 on Lobsters and 1 in engineering communities.
  • A classic. People kept recommending it from 2014 to 2021.
  • Presented by Bob Spence, Professor at Imperial College London

Beginner. No background in the topic needed.

110K views13 years ago8 recommendations

Programming languagesHistory and cultureRetro computingHistory of computing

Bob Spence demonstrates the APL programming language on a terminal in 1975, showing its unique syntax and interactive capabilities.

1975 live demonstration of the computer language APL (A Programming Language) by Professor Bob Spence, Imperial College London. Bob joined the staff of Imperial College in the 1962 and is now Professor Emeritus in EEED. His field of work has ranged from engineering design, to human-computer interaction (HCI) and along the way is credited with the invention of the first 'focus+context' technique, the Bifocal Display (aka Fisheye lens) featured in another video. For more:wwwf.imperial.ac.uk/blog/videoarchive/2010/01/01/research-an…

Why it's here

8 people recommend this

What people say. Highly recommended as a classic, charming introduction to the APL programming language and its history.

inactive-useron Lobsters • Recommends

APL demonstration 1975
11View on Lobsters

jmon Lobsters • Recommends

APL demonstration 1975 - YouTube
8View on Lobsters

progmanon Hacker News • Recommends

On “J for C Programmers”

APL without native fonts isn't fun at all. This is real fibonacci in APL: link link This is a nice introduction into APL: link to this video And this is how APL is applied in the right way: link
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cgrubbon Hacker News • Recommends

On “GNU APL 1.7 Released”

I think this is a good youtube video for someone starting from zero: link to 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
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curiousgalon Hacker News • Recommends

On “J can look like APL or English”

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. link to this video
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hhas01on Hacker News • Recommends

On “A+, the Programming Language of Morgan Stanley”

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: link to 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.
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jazzyjacksonon Hacker News • Recommends

On “IBM unveils 127-qubit quantum processor”

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) link to this video
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u/hou32houin r/ProgrammingLanguages • Recommends

APL demonstration 1975
1View on Reddit

sanarotheon Hacker News • Mentions

On “Show HN: A Fortran web framework”

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: link to this video
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3rdAccounton Hacker News • Mentions

On “My dad’s resume and skills from 1980”

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. link to this video
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m463on Hacker News • Mentions

On “Python should take a lesson from APL: Walrus operator not needed”

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: link to this video I don't know whether to think "thank goodness for unicode" or "unicode is an enabler of problematic practices" :)
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u/non_clever_nameAréin r/ProgrammingLanguages • Mentions

On “July '18 monthly "What are you working on? How is it coming along?" thread”

>APL was so perverse, that it even had overstruck characters; ie. you back up and overstrike the letter to mak a new combo letter. When some of the earliest APL computers were literally typewriters that doesn't seem so weird. >he figured that people could easily remember 100 operators and their precedence and whether they were left-associative or right-associative. APL doesn't have operator precedence and all operators are right-associative. Execution always goes right-to-left. `5×3-1` is 10, not 14. It's really quite a bit easier than other languages. > LISP is an interesting language, because it has been revived several times, because people just can't stop engaging in optimistic thi…
2View on Reddit

u/Gawwadin r/compsci • Mentions

On “What in your opinion is the most esoteric and difficult to learn language, tool or technology that sees serious use commercially?”

This guide makes it fairly easy to understand.
1View on Reddit

u/PurpleUpbeat2820in r/ProgrammingLanguages • Mentions

On “Favorite Feature in YOUR programming language?”

> Not really a language but I agree. Yeah. I'm not sure what you'd even call it but it is clearly related to: * Lisp's REPL * APL's REPL * Smalltalk's IDE * Mathematica's notebook interface Whatever you call it, I wish people took this aspect of programming languages more seriously!
1View on Reddit