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The Idea of Lisp

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Re: The Idea of Lisp

#31

Post by mroll »

qwertyuiop924 wrote: post #26
mroll wrote: post #25

Earlier quoted context omitted.

If you like everything being an expression, check out tcl. A lot of ideas from lisp show up in tcl, especially the idea of everything as an expression. Tcl embodies this idea while also having the look of an algol-like language. Funny it can pull this off while having basically no syntax.

TCL, while it has its warts, is a really cool language. I mean, it even basically has fexprs, something most Lisps put by the wayside years ago. When you don't actually care about speed, you can do some pretty cool stuff.

Yeah the level of dynamicness (dynamism?) you can get in tcl is unparalleled as far as I can see. Having no types or syntax and access to the entire runtime at any point in the program opens up all kinds of crazy doors. But you're right, that slows it down.

But you might be interested to know there is currently an effort to get Tcl to compile to native/near-native code. Here is a paper on the new techniques being developed and a link to a talk given by one of the lead tcl core team members.

http://www.tcl-lang.org/community/tcl2015/assets/talk14/TheT...

https://www.youtube.com/watch?v=RcrqmZV88PY&t=38s

Re: The Idea of Lisp

#32

Post by arethuza »

agentgt wrote: post #2

The conditional expression or more specifically everything being an expression is my favorite thing about Lisp. I did not know that McCarthy pushed to add it to Algol which apparently today is the ternary operator for most languages. It is annoying that so many languages (C, Java, C#, etc) have both a conditional statement (if-else) and conditional expression (ternary ?:). Really the if-else should be an expression (…

It's been a while since I used Common Lisp but isn't it recommended to use "if" for conditional expressions and "when"/"unless" for conditional statements?

Re: The Idea of Lisp

#33

Post by pjmlp »

qwertyuiop924 wrote: post #26
mroll wrote: post #25

Earlier quoted context omitted.

If you like everything being an expression, check out tcl. A lot of ideas from lisp show up in tcl, especially the idea of everything as an expression. Tcl embodies this idea while also having the look of an algol-like language. Funny it can pull this off while having basically no syntax.

TCL, while it has its warts, is a really cool language. I mean, it even basically has fexprs, something most Lisps put by the wayside years ago. When you don't actually care about speed, you can do some pretty cool stuff.

Yes, I worked on a startup that did pretty much something like Ruby on Rails, but with TCL, inspired by AOLServer.

The speed critical parts were written in C and loaded as TCL extensions.

Back in the first .com wave.

It also taught me to never again use a programming language without JIT/AOT compiler on their standard toolchain for heavy loads.

Re: The Idea of Lisp

#34

Post by zodiac »

wyager wrote: post #16

> This is a proof by construction that the language is computationally complete. The definition of Turing completeness in the article is not correct. A language being able to execute programs written in itself is not a sufficient condition of Turing completenes. Trivial example: define a language with one pre-defined term, x, which is a routine that takes as input a string, checks if it's "x", and executes it if it i…

I agree...I think a real "proof by construction that the language is [Turing] complete" would just be an interpreter for Turing machine programs written in Lisp, which is pretty boring.

Re: The Idea of Lisp

#35

Post by sorokod »

agentgt wrote: post #2

The conditional expression or more specifically everything being an expression is my favorite thing about Lisp. I did not know that McCarthy pushed to add it to Algol which apparently today is the ternary operator for most languages. It is annoying that so many languages (C, Java, C#, etc) have both a conditional statement (if-else) and conditional expression (ternary ?:). Really the if-else should be an expression (…

if-else is an expression in Kotlin ( https://kotlinlang.org/docs/reference/control-flow.html )

Re: The Idea of Lisp

#36

Post by Blackthorn »

erik14th wrote: post #18

I wonder why lisp isn't as popular as say python for AI, ML, and stuff. I see these fields as having a strong academic tone, and it feels like racket or clojure could be bigger when it comes to that.

Well, it was. Specifically, Common Lisp was. But that language's standard was etched in stone in 1994 whereas languages like Python (where most deep learning user-facing code is done) continue to evolve.

I think Python really took off for that because it already had quality and widely-used libraries for writing the code in Python and doing the work in a more efficient place (numpy, scipy). Clojure has one of those for matrix multiplication but not much else there, and I'm not sure Racket has anything at all.

Re: The Idea of Lisp

#37

Post by pjmlp »

mtrimpe wrote: post #22
erik14th wrote: post #18

I wonder why lisp isn't as popular as say python for AI, ML, and stuff. I see these fields as having a strong academic tone, and it feels like racket or clojure could be bigger when it comes to that.

Because Common Lisp was the language for AI before the big AI-winter hit and it's now associated with approaches to AI that don't actually work. Also a lot of the latest AI is hyper optimized data crunching on GPUs which isn't necessarily one of lisp's strengths.

Well, actually *Lisp was a thing.

I think it is also a matter of culture, probably if the likes of AMD and NVidia cared, they could invest some money into making such languages run properly on GPGPUs, instead of leaving it to researchers alone how to target PTX and ROCm.

On the other hand something like C++17 would already offer many of the Lisp benefits, even if a bit uglier.

Re: The Idea of Lisp

#38

Post by groovy2shoes »

lispm wrote: post #24
agumonkey wrote: post #9

Earlier quoted context omitted.

While ML was the meta language for a theorem prover. Funny how these were side effects.

And ML was originally written in Lisp. https://github.com/theoremprover-museum/LCF77/tree/master/sr... https://github.com/theoremprover-museum/HOL88/tree/master/sr...

And [O]Caml was originally called "Le-ML" because it was written in Le-Lisp (and targeted the same VM, LLM3).

Re: The Idea of Lisp

#39

Post by pjmlp »

lolive wrote: post #4
kluck wrote: post #3

Lisp was developed because McCarthy needed a tool for experimenting with AI. Found a video of McCarthy talking about AI: https://www.youtube.com/watch?v=Ozipf13jRr4 And if anyone cares, here is nice Shirt with McCarthy on it ;) https://www.teepublic.com/t-shirt/666689-john-mccarthy-lisp-... I think it should be mandatory for CS students to implement their own little Lisp using the building blocks McCarthy described!…

Is there a kind of walkthrough/tutorial about how to develop a little Lisp interpreter? That sounds like a fun experiment. PS: Sorry, I am a Java OO developper. But I like to learn :)

Yes, this quite good book, "Lisp in Small Pieces"

https://www.amazon.com/Lisp-Small-Pieces-Christian-Queinnec/...

Re: The Idea of Lisp

#40

Post by agumonkey »

lmm wrote: post #19
agumonkey wrote: post #9

Earlier quoted context omitted.

While ML was the meta language for a theorem prover. Funny how these were side effects.

If there's one thing I've learned from programming it's that to build anything good you have to be driven by real use cases.

Just like nature.
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