Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

What Is a Logo-Like Language?

maxhallinan.com

Post reply on HN
Print view View original

31–39 of 39 posts

Re: What Is a Logo-Like Language?

#31

Post by bharvey »

DonHopkins wrote: post #27
justin66 wrote: post #25

Earlier quoted context omitted.

The person I would ask is Brian Harvey, but that's just a guess. It sounds pretty funny regardless.

Good guess: I was just discussing it with Brian Harvey, Ken Kahn, Andrea diSessa, and Leigh Klotz, who said he has a copy, which I've asked him to please share! Then I saw this LOGO discussion. Plate of shrimp! I love the great work Brian Harvey and Jens Mönig have done with Snap! It's like a non-watered-down version of Scratch, with the full power of Scheme (first class functions, lexical closures, special forms, co…

I have to confess, that function, even though I always call it Y when I write it so people will get what it's about, isn't a combinator at all. Writing a real Y combinator in an applicative-order language is possible but complicated, so I never do it. :-) (The difference is that this function takes a _two input_ function as input and supplies itself as its first input. Really it should take a one-input function and magick that into a two-input one first.)

Re: What Is a Logo-Like Language?

#32

Post by DonHopkins »

bharvey wrote: post #31
DonHopkins wrote: post #27

Earlier quoted context omitted.

Good guess: I was just discussing it with Brian Harvey, Ken Kahn, Andrea diSessa, and Leigh Klotz, who said he has a copy, which I've asked him to please share! Then I saw this LOGO discussion. Plate of shrimp! I love the great work Brian Harvey and Jens Mönig have done with Snap! It's like a non-watered-down version of Scratch, with the full power of Scheme (first class functions, lexical closures, special forms, co…

I have to confess, that function, even though I always call it Y when I write it so people will get what it's about, isn't a combinator at all. Writing a real Y combinator in an applicative-order language is possible but complicated, so I never do it. :-) (The difference is that this function takes a _two input_ function as input and supplies itself as its first input. Really it should take a one-input function and m…

So technically, that's a "Y Not-Combinator"?

Re: What Is a Logo-Like Language?

#34

Post by justin66 »

bharvey wrote: post #30
WorldMaker wrote: post #6

Earlier quoted context omitted.

I seem to recall at least one Logo I used as a kid had an "advanced mode" that in hindsight boiled down to S-Expressions and several more Lisp functions added to its standard library. Wish I could recall which Logo that was. Maybe one of the later LCSI builds (Apple Logo or IBM Logo), but possibly some version of Lego's TC Logo?

Have a look at Berkeley Logo, https://cs.berkeley.edu/~bh/logo.html About S-expressions, you can fully parenthesize everything if you want. But Logo uses square brackets, not parens, as list delimiters, so you still have to do a little bit of tokenization.

Thanks for making your Logo books available!

Re: What Is a Logo-Like Language?

#35

Post by justin66 »

9214 wrote: post #10

Rebol and Red [1] are the only languages that I know which acknowledge having Logo heritage in their design and philosophy. Speaking from my experience, I can tell that working in them is indeed a deeply embodied microworld-like experience, they way author describes. Manipulating homoiconic structures feels highly spatial, as if you're molding a clay with your own hands, or rather palpating the Urschleim. High polymo…

Anyone interested in checking out the MIT Press Exploring Logo books should check out bharvey's link, he's shared the first three books of the series (along with other good stuff) on his web page.

Re: What Is a Logo-Like Language?

#36

Post by toontalk »

Regarding

...the elements of a language are features of a world I inhabit:

Environments are values floating above my head. I have an urge to glance up when I’m thinking about what’s in scope. A closure is a one-way tunnel or pipe or wormhole back into the function environment. But the program itself can’t flow through the pipe. Asynchronous control flow is a stream that I imagine myself floating down. I think about where the stream will take me. Functors are giant structures, like a sculpture by Richard Serra. Functor operations act like cranes, helping me to move around those structures.

27 years ago I began working on a programming language in which computational abstractions had concrete animated analogs [1]. ToonTalk was my attempt to make a Logo for the 90s. You programmed in a virtual world where you trained robots to put things in boxes, give birds messages to deliver, etc. The mappings are: computation: city, actor or process or object: house, methods: robots, method preconditions: contents of thought bubble, method actions: actions taught to robot, tuples or messages or vectors: boxes, comparison tests: scales, actor spawning: loaded trucks, actor termination: bombs, constants: numbers, text, and pictures, channel transmit capabilities: birds, channel receive capabilities: nests, program storage: notebooks.

ToonTalk became free and open source 12 years ago. 5 years ago I had time to re-implement much of it as a web app [2]. But as Don Hopkins wrote - I'm focussed now on adding AI to Snap!

[1] http://www.toontalk.com [2] https://toontalk.github.io/ToonTalk/

Re: What Is a Logo-Like Language?

#37

Post by ksaj »

jhbadger wrote: post #5

Logo is actually more than just a toy language for turtle graphics. It's a serious language with a lot of inspiration from Lisp (although not using sexps).

As an example: NetLogo is most definitely not a toy language. Especially NetLogo3D. You'll see both of them in a lot of alife and ai demos.

Re: What Is a Logo-Like Language?

#38

Post by larsbrinkhoff »

DonHopkins wrote: post #27
justin66 wrote: post #25

Earlier quoted context omitted.

The person I would ask is Brian Harvey, but that's just a guess. It sounds pretty funny regardless.

Good guess: I was just discussing it with Brian Harvey, Ken Kahn, Andrea diSessa, and Leigh Klotz, who said he has a copy, which I've asked him to please share! Then I saw this LOGO discussion. Plate of shrimp! I love the great work Brian Harvey and Jens Mönig have done with Snap! It's like a non-watered-down version of Scratch, with the full power of Scheme (first class functions, lexical closures, special forms, co…

LLOGO runs on a PDP-10 emulator, including the Knight TV display.

Video of LLOGO demo by Henry Lieberman: https://www.media.mit.edu/videos/144-lisp-logo-demonstration...

Re: What Is a Logo-Like Language?

#39

Post by Doxin »

thesuperbigfrog wrote: post #2

Python offers a nice Logo-like environment using "import turtle". https://docs.python.org/3/library/turtle.html

That module is great fun to mess around with. I've made a program that uses it to plot the Python logo[1]. I had intended to also have it plot the correct gradient but I had trouble getting the trapezoid filling algorithm working correctly at the time.

[1] https://gist.github.com/SuperDoxin/d7bb473dcec7e1c55f48

Post reply on HN