Lisp, The Quantum Programmer's Choice

Lisp, The Quantum Programmer's Choice - Computerphile

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6 жыл бұрын

Quantum computing is so new it needs a flexible language for programming - Robert Smith of Rigetti Quantum Computing explains why he uses this 60 yr old language for cutting-edge work.
Meta-Programming: Coming Soon
PDP-11 & Zork: • DEC PDP-11 & Zork - Co...
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This video was filmed and edited by Sean Riley.
Computer Science at the University of Nottingham: bit.ly/nottscomputer
Computerphile is a sister project to Brady Haran's Numberphile. More at www.bradyharan.com

Пікірлер: 302

@marsgal42 6 жыл бұрын

When I first encountered LISP back in my undergrad days the prof described it as an interesting language where you can write interesting programs that do interesting things.

@DarkShroom 6 жыл бұрын

so as unspecific as this guy?

@anastacioguerrero1527 6 жыл бұрын

Used it in autocad back in the day, except they autolisp, before windows version of the program came out.

@r.pizzamonkey7379 3 жыл бұрын

@@DarkShroom Well it's kind of the condemnation of faint praise, since an "interesting" program is not necessarily a useful program. That's kind of how I felt about haskell. Great for data processing, great at abstract algorithms, a headache to make anything real with.

@miikavihersaari3104 Жыл бұрын

Interesting!

@kMv9C3N9 6 жыл бұрын

I wish that this video would *show* how Lisp is a good language, rather than just saying it can do this, that, and the other thing.

@unlokia 6 жыл бұрын

That's what Prof. Brailsford would have done, yep.

@JamEngulfer 6 жыл бұрын

jmw150: That doesn't show anything to do with how it's better for quantum programming.

@JovanKo314 6 жыл бұрын

"Guugu Yimithirr is a great language that gives you a better sense of direction." "Oh really? How so?" "Why don't you just learn the language?"

@user-iu1xg6jv6e 6 жыл бұрын

Next vid: *Meta-Programming: Coming Soon*

@webgpu 6 жыл бұрын

exactly. this video is useless (sorry, i can't mince words)

@BryonLape 4 ай бұрын

Of the variety of languages I've learned over the last 40 years, Lisp is the only one that spoke to me.

@ElagabalusRex 6 жыл бұрын

Like with many Computerphile videos, I just can't appreciate why this topic is important without concrete examples. Glad to see another video is on the way.

@brightshadow9480 6 жыл бұрын

This is a sermon singing the praises of Lisp, but providing little beyond 'Lisp is great!'. If you want to know more about the actual details of the language, consult another video.

@qwertyman1511 6 жыл бұрын

their video on imperative vs functional actually explains a bit of haskell. we don't see anything here.

@drunkenmonkey1457 6 жыл бұрын

@jmw150 No one asked for them to teach us the language, just to show what they were talking about. They presented an argument, but failed to support it properly.

@webgpu 6 жыл бұрын

exactly. this video is useless (sorry)

@Rensoku611 6 жыл бұрын

jmw150 brah you got owned in all the other comments

@squirlmy 3 жыл бұрын

@@Rensoku611 I don't think so. And do you just mean the comments here, because he's been a much busier beaver than that!

@evanbelcher 6 жыл бұрын

/examples/

@tohopes 6 жыл бұрын

HAVE U TRIED GOOGLING LITERALY ANY ISNTRUCRTIN MANUAL ON LTHKEN O NASUYFGN? ANWEFNAETUGAO SDCIONASDO CINASODI CN -jmw150

@TheCandyDragon 6 жыл бұрын

@TheScabbage 6 жыл бұрын

+tohopes I didn't get the joke till I read other comments +1 for satire

@user-iu1xg6jv6e 6 жыл бұрын

In next video *Meta-Programming: Coming Soon*

@bujarmurati3004 6 жыл бұрын

tohopes this should become a meme

@aditya95sriram 6 жыл бұрын

loved this intro, would be great to have some more concrete examples of how he uses it in quantum computing

@alanvitullo 6 жыл бұрын

...so this is an intro video in a series? My vote is for more code please!

@BananaTV1978 5 жыл бұрын

Geez comments-people, chill out! The video is titled "programmers choice" with a programmer explaining WHY it's his choice ... that's it! It's conversational. Listen to what he's saying and then go find videos focusing on the code if you want to know more.

@4BoltClevo 6 жыл бұрын

I was waiting for him to write some code on his paper and then the video ended. I didn't learn anything...

@4BoltClevo 6 жыл бұрын

Hey slick, congrats, you found google. Why don't you send me the lmgtfy 1+1 link for a real original joke?

@aufarz 5 жыл бұрын

(+ 1 2)

@afonsorafael2728 3 жыл бұрын

(print “hello world”) There you go, now go search for a interpreter

@prism223 Жыл бұрын

For all those wishing the video went into details about why Lisp is useful: Lookup SICP from the legendary MIT curriculum, for which there are also lecture videos by one of the authors Gerald Jay Sussman. The language is timeless so even the old materials are perfectly fine to study today.

@mendelovitch Жыл бұрын

"The Little Schemer" is a fantastic book, too. Pithy and fun. It has many sequels.

@shmallacy 6 жыл бұрын

17 people didn't find an editor that balances parentheses for them.

@completemadlad15 4 жыл бұрын

try racket

@beantown_billy2405 3 жыл бұрын

@@completemadlad15 paredit too

@theswip3r 6 жыл бұрын

Hadn't thought Lisp was that flexible. I'm pretty burnt out from template programming in C++, so I ought to give Lisp a try.

@ACium. 10 ай бұрын

How is it going now?

@ZeedijkMike 6 жыл бұрын

I worked with _Auto_ LISP in the late 80'ies early 90ies. I think/presume they are related. It was one of the first languages I actually used. Strange syntax - but when you get used to it, it's quite fun and amazing. Even made a Mandelbrot Fractal program for AutoCAD. Slow as hell but fun to build.

@ManuTheGreat79 6 жыл бұрын

Yeah, I do this today. I should try making the Mandelbrot Fractal some day, sounds fun :)

@jhbonarius 6 жыл бұрын

Ha, LISP! yes! This was one of the first languages I learned. It was so long ago, I had forgotten the name.

@kewakl8891 6 жыл бұрын

I am glad that there is a follow-on video. We waited for 6 minutes 12 for any examples to justify his 'fondness' of Lisp. Nothing. Not a bit of code - except a allusion to an assembler-version of a For Loop construct.

@HerrLavett 6 жыл бұрын

Show me some code!

@pladimir_vutin 3 жыл бұрын

mate have patience, this guy is talking meta, his speech is important imo.

@mistress_remilia 6 жыл бұрын

Finally a video with Lisp in it! My favorite language

@PaulaJBean 6 жыл бұрын

@j-r-hill 3 жыл бұрын

He is saying that Lisp is suitable to quantum computing (qc) because qc is new, and Lisp allows you to extend the language extremely easily. The bonus video goes into more detail

@eknuds Жыл бұрын

Great! Twenty five years ago when I was using XEmacs as my C editor working at a startup I used to have it do things like generate header files. Then after we went public I had it load stock prices from Yahoo and show a ticker on the Modeline.

@AndersJackson 6 жыл бұрын

You might also want to look into Prolog, which is also good in writing languages and extend the language itself. But yes, I like Common Lisp, it was my fist language in Computer Science, Uppsala University. Also learned to code in Erlang and Prolog there. And yes, Lisp IS a functional, symbol manipulation language. It was designed from the beginning to express the lambda calculus, the basis of functional programming. Yes, it has a great macro language and it is very flexible. And yes, you become a better programmer by learning to program in Lisp.

@PaulaJBean 6 жыл бұрын

Prolog has strong pattern matching abilities, like Haskell.

@AndersJackson 6 жыл бұрын

Actually, Haskell, Ocaml and Erlang has only pattern matching. Prolog has Unification, which is a much stronger mechanism then pattern matching. You can have variables on each side in a Unification, but you can only have variables on one side in a pattern matching expression.

@ab_synth 6 жыл бұрын

I can't believe I took a couse in university which started with "lisp is a functional language" and KZfaq is now informing me otherwise

@WorBlux 6 жыл бұрын

But you can change state, do I/O and sequence operations in a way that doesn't require special syntax,

@speedbump0619 6 жыл бұрын

exactly. The existence of 'set' means it's not purely a functional language

@slowpoke126 6 жыл бұрын

There's no such thing as a functional language.

@florianp4627 6 жыл бұрын

More about how Robert does his coding for quantum computing please!

@Wyklepheph 2 жыл бұрын

Nim is very similar in that you can extend the language and create new syntax and new functionality, and you get the bonus that nim code is a lot nicer to look at

@yash1152 2 жыл бұрын

> _"nim language - extensibility + nice looking"_ hey, any reference video?

@Adam-jp8bm 6 жыл бұрын

Just want to say, Most quantum programs are not actually using lisp, most are using small, proprietary DSLs for quantum computing, such as IBM's OpenQASM

@squirlmy 3 жыл бұрын

The source code was released as part of IBM's Quantum Information Software Kit

@PaulPaulPaulson 6 жыл бұрын

I'd like to hear about "Smalltalk" next

@thaddeuspawlicki4707 6 жыл бұрын

PROLOG! Now THERE is a real language! Because . . . . "jwm150's FEELINGS"!

@draakisback 6 жыл бұрын

Smalltalk is a great language with some fairly revolutionary ideas like the images (which are used heavily in dart as snapshots).

@DarkShroom 6 жыл бұрын

yes i love the way it fits on an punchcard! awesome, that's just what i want out of a modern language, thanks

@DarkShroom 6 жыл бұрын

i recon i'm gonna have 1000 primes when i get my mail next friday

@Biped 6 жыл бұрын

mhh. maybe I should look into lisp myself a little more before but... Defining a concept and later working with that... can't every ordinary language do that? I mean if there wasn't a for loop previously you could surely just define a function for() with more basic instructions inside, right? Maybe lisp goes deeper. I should check that out.

@nikonyrh 6 жыл бұрын

An biased suggestion: try Clojure which runs on the JVM with Nightcode as your first IDE ;) I was truly amazed! For sure almost all languages are Turing-complete but some take just 1 line of code and others might take a dozen or more.

@TribeWars1 6 жыл бұрын

Well not in C at least. Try writing your own for loop expression (call it myfor() or whatever) and it won't work. The arguments get evaluated before they get passed to your for loop construction.

@zebop111 6 жыл бұрын

Use functions. typedef void (*for_init_t)(void*); typedef BOOL (*for_cond_t)(void*); typedef void (*for_loop_t)(void*); typedef BOOL (*for_body_t)(void*); void* myfor(void* ctx, for_body_t fb, for_init_t fi, for_cond_t fc, for_loop_t fl) { fi(ctx); while (fc(ctx) && fb(ctx)) fl(ctx); return ctx; }

@dangnabbit1379 6 жыл бұрын

zebop111 Nice

@jimmamd123 6 жыл бұрын

I can't click on the “meta-programming” video at the end. There's no link and does not appear in the general search. What happened to it?

@kewakl8891 6 жыл бұрын

I always found Lisp to be defun fun() Oh, I used AutoLisp to add functionality to AutoCAD

@SwordQuake2 6 жыл бұрын

So is there an extra bit or not?

@Ninja9191 6 жыл бұрын

Haven't worked with Lisp, but I have used Scheme. These languages are fun to use.

@Elite7555 6 жыл бұрын

And they are hard to maintain (write only), macros can make them incredible hard to use (new semantics), and they are pretty slow because of language design. They might be "fun", but I would never use them for serious work, although there are some pretty big projects in Clojure.

@unlokia 6 жыл бұрын

Scheme, or "Thceme"? Thorry, I have a lithp.

@Ninja9191 6 жыл бұрын

Elite7555 oh yeah, I agree. I think they're useful for understanding the programming concepts, but I can see how it might become a mess if I start to use them for large projects. Though the design principles are also the things that make them appealing (keeping libraries small, having simple code, etc)

@krasen4oo 6 жыл бұрын

Check your facts. There are not much slower than C since the 90s.

@johannesdegen9225 6 жыл бұрын

Very funny Igor.

@toyuyn 6 жыл бұрын

I remember xkcd's author's a fan of Lisp...didn't think much of it when he mentioned it in his comics, but now i'm intrigued.

@gummansgubbe6225 6 жыл бұрын

A decade since my loops looked like for(int i=....). Now I am counting cores and dividing into shared/private variables. I have never seen a quantum computing problem though.

@carlfranz6805 6 жыл бұрын

Wow. That was astonishingly non informational.

@beantown_billy2405 3 жыл бұрын

There was a lot of information there, but it's not for beginners. I mean... it's about how homoiconicity allows easier metaprogramming to create new language concepts for quantum computing. It's a lot to unpack. I felt that way when I first read the docs for Clojure transducers - "transducers are composable algorithmic transformations that are decoupled from their input data" - it sounds like jibberish to anyone who works down low on the abstraction ladder.

@Kalernor 6 жыл бұрын

Great, now I want to learn Lisp.

@christopherbravo2383 6 жыл бұрын

you should check out Racket if you haven't already!

@timsiwula5734 4 жыл бұрын

before i knew what macros were i loved to use m4 directives when i was learning c

@rztrzt 6 жыл бұрын

Why was the video cut short?

@maciejmanna9246 6 жыл бұрын

Ever tried template metaprogramming in C++ (just replace drowning in round brackets with drowning in angle brackets :P)...

@dariusduesentrieb 6 жыл бұрын

ooh c++ templates are lovely

@iseslc 6 жыл бұрын

At a glance, yes. The deeper you go, the crazier it gets.

@maciejmanna9246 6 жыл бұрын

Yep, recursively crazier... Ad infinitum...

@Roxor128 6 жыл бұрын

Amusingly, C++ templates are Turing Complete, but were not intended to be so.

@katrinal353 6 жыл бұрын

Yeah, I love building template libraries, how fun, that's exactly what I signed up for... lol

@jessstuart7495 6 жыл бұрын

Lisp owes it's great utility to the power of the cons-cell data structure.

@matt_b... 6 жыл бұрын

A Colonel of an idea. Not quite as advanced in rank as a General idea, but still a solid idea nonetheless.

@user-vz7mu4su9n 6 жыл бұрын

matt b, it is a pretty major concept.

@letao12 6 жыл бұрын

Argh, everyone else's ideas are better than my Private thoughts.

@benjaminmiddaugh2729 6 жыл бұрын

I'm not sure I can contribute anything that would rank among the ideas already present.

@lithiumdeuteride 6 жыл бұрын

So you're keeping your ideas Private?

@puellanivis 6 жыл бұрын

Reading these puns is corporal punishment…

@delwoodbarker 6 жыл бұрын

Webmaster, the two floating popups to related articles are covering up the two static links to related articles. The latter are inaccessible. Both in Chrome and Safari.

@Misterlikeseverythin 6 жыл бұрын

How can you use x86 architecture for quantum computing? It seems x86 would need some ASIC/FPGA to provide an interface between that and the wires going to quantum computer.

@1906Farnsworth 6 жыл бұрын

I noticed there was no discussion of having someone else understand his code. When he extends the language, does he publish an API? Is the code itself documented? Maybe it won't matter... Maybe it will.

@j7ndominica051 6 жыл бұрын

Cakewalk Application Language scripting was based on this. The weirdest concept for me was that the plus, minus, increment, equals and other operators are written first. But surprisingly it started to make sense soon.

@crnkmnky 2 жыл бұрын

Was that a scripting language for the Cakewalk/Sonar audio workstation?

@yash1152 2 жыл бұрын

it sounds similar to the RPN (reverse polish notation) for calculators, except that symbols come first lol

@unlokia 6 жыл бұрын

You needed to have had Richard Stallman doing this video; then again, I supposed you wanted it to be less than 2 hours in length, so... ... OR... someone with a lithp...

@luckylove72 4 жыл бұрын

unlokia Ask Knuth

@IoCalisto_ 6 жыл бұрын

What's the difference between this and defining functions?

@rkpetry 6 жыл бұрын

*_...quantum computing is where they simulate a neutron decaying in less than 700 seconds half-life if you can wait long enough for the full answer..._* (p.s. 700 was updated to 880±)

@TaylorTheOtter 6 жыл бұрын

I’m glad I decided to try lisp out. It’s a great programming language. I don’t know why I like it so much though but to me it feels really intuitive, even after only 2 days of messing with it. With python, that took me a month. After 4 years of Python being in all 5 of my top 5 list of favorite programming language, lisp has crawled it’s way up there to 5th place. Places 1-4 are still Python though...

@diegonayalazo 2 жыл бұрын

Me too. Then I gravitated towards Clojure.

@readein 3 жыл бұрын

I found this video very interesting, and didn't come into it expecting a tutorial or a deep explanation of the code itself. The title didn't infer either of those things. It would take 2 seconds to find the code if you really wanted to.

@readein 3 жыл бұрын

@Tyler Does it matter which verb I chose? Infer works in this context also.

@ricardopalacios5968 6 жыл бұрын

Just bought 'Structure and Interpretation of Computer Programs' by Abelson and Harold. I used to know BASIC when I was a little kid and I am just getting back into computer science. I think my best bet is to start off fresh with Lisp. Lectures from Abelson and Harold are available through MIT OpenCourseware.

@sawyerrken8112 3 жыл бұрын

How the things go with the book? Did it help?

@ricardopalacios5968 3 жыл бұрын

@@sawyerrken8112 It actually inspired me to go back to school and I'm currently working on my bachelor's in computer science. The plan is to get my doctorate's degree.

@pladimir_vutin 3 жыл бұрын

@@ricardopalacios5968 wish the bests for you. get into system programming. I am a student myself. i however regret becomimg one, since i'm in germany and it's more of a burden .

@ChronicWhale 6 жыл бұрын

I enjoyed the video but you don’t show an example of the code, not even something simple, would be better if you showed us how some of the concepts he was exposing actually appear

@sonic-du1hw 6 жыл бұрын

I love Computerphile!

@yash1152 2 жыл бұрын

so, the meta-programming video is still in "coming soon" after 4 years 👀?

@IproCoGo 6 жыл бұрын

The end of the channel's videos cut off mid-sentence. Is there another site where we see the entire video? Thanks.

@PeterAbt 6 жыл бұрын

So how can we actually add two numbers with quantum mechanics? 🤔

@Edu4Dev 3 жыл бұрын

That's exactly my efforts here in Brazil, tks for posting :D

@CJBurkey 6 жыл бұрын

I feel like Marc Grenville-Cleave is an important name to know, but I don't, is that bad?

@Seppes94 6 жыл бұрын

I also have no idea, who he was. Just leaving a comment to get notified.

@detaart 6 жыл бұрын

The person in the video.

@timh.6872 6 жыл бұрын

False, take a look in the description.

@tohopes 6 жыл бұрын

Lots of vague assertions with no code? What kind of computer programming video is this?

@tu_nonna_emiliana 6 жыл бұрын

Ye yu, how about Mark Grenville-cleave? Who was him?

@webgpu 6 жыл бұрын

are you all afraid of saying this video is useless? not only that, but you went on and "like"d it???

@Alphaaa13 6 жыл бұрын

So by inventing the fitting langue on the way doesn't that result in noone being able to comprehend the done work in a reasonable time?

@brentgordon3801 6 жыл бұрын

Which variation should I learn

@JimFortune 6 жыл бұрын

It gets compiled to machine language, not assembly, right?

@dannygjk 6 жыл бұрын

Yes he must have misspoken.

@quadricode 6 жыл бұрын

They are one to one.

@CODMarioWarfare 6 жыл бұрын

It compiles to assembly and then the assembler assembles machine code

@JimFortune 6 жыл бұрын

quadricode No, they're not. Simple example; Relative addressing.

@DoubleOhSilver 6 жыл бұрын

@CODMarioWarfare No it Doesn't, it compiles directly to machine code. There is no reason to generate assembly just to convert that to machine code

@grivar 6 жыл бұрын

I can't decide if that's Tom Scott or John Green...

@vicplichota 6 жыл бұрын

Lisp and Forth changed my life.

@SenorQuichotte 6 жыл бұрын

lisp is great for creating AI, NN, fuzzy logic, machine learning.

@barefeg 6 жыл бұрын

why not use Mathematica for example? I use it to "program" the theory rules or formalism, so i can do physics computations automatically

@pedrov8868 3 жыл бұрын

For custom quantum programming you wouldn't be able to have the flexibility

@MamboBean343 6 жыл бұрын

4:29 I thought most time programming is spent debugging!

@squirlmy 3 жыл бұрын

he is counting "debugging" as thinking. It can be tedious, but its still thinking. Try to debug anything without thinking. I

@krish2nasa 6 жыл бұрын

A video on FORTH please, Thanks a lot.

@meanmikebojak1087 6 жыл бұрын

Krish Rao Thanks I was just about to suggest Forth. It compiles as you code, and its extendable.

@PaulaJBean 6 жыл бұрын

The boot menu of FreeBSD is written in Forth.

@Maric18 6 жыл бұрын

how does lisp do this? this video is a (lengthy) intro ... and then it just stops o.0

@spikeevans1488 6 жыл бұрын

Doesn't forth also meet your criteria?

@davidwuhrer6704 6 жыл бұрын

Doesn't every language?

@chswin Жыл бұрын

Do the parentheses also become entangled?

@suicidalbanananana 6 жыл бұрын

What about microsoft's Q# ?

@seasong7655 5 жыл бұрын

I think not just lisp but every new language you learn, teaches you to look at problems in a different way

@MyNameIsPetch 6 жыл бұрын

Not too sure about that sun example...

@RomyIlano 5 жыл бұрын

He’s so cool!

@minefunrapguy 6 жыл бұрын

Nice

@denizcanbillor9951 6 жыл бұрын

Thank you

@normannormiemates4844 6 жыл бұрын

Lisp programmers are just so _out there_

@user-zu1ix3yq2w 6 жыл бұрын

Once you get it, you understand.

@VoilaTadaOfficial 6 жыл бұрын

Is it just me or does Computerphile's endslates never actually have clickable links? :< I want to watch that meta-programming video but it's not clickable. (And yes I'm aware the links are usually in the description, but it's more intuitive to click the annotations.)

@TheDuckofDoom. 6 жыл бұрын

Yes, I have noticed they often are TBD.

@abigailhodge6588 6 жыл бұрын

Great video! The first language I learned was racket, which is lisp-based and you're totally on the mark on, for example Java, being a lot more constraining---switching from racket to Java was a bit of a mind screw

@dannygjk 6 жыл бұрын

Java is garbage anyway it should be banished.

@GuitarDhyana 5 жыл бұрын

This is all true - and lisp is great - however you don’t really demonstrate that will prove your assertions.

@redd_cat 6 жыл бұрын

Lithp is a great language!

@luezma 6 жыл бұрын

You forgot to add the git proyect link

@michelef406 6 жыл бұрын

This video is just a lisp service.

@diegonayalazo 2 жыл бұрын

Thanks

@TheDavidlloydjones 5 жыл бұрын

LISP almost vanished in the 1970's: even with outsourcing to China, the entire world was incapable of producing a sufficient supply of parentheses. Advanced automation -- the production of parentheses in pairs -- enabled it to hang on for a while, but it was always a struggle. Quantum computing is its only hope: propositions which simultaneously are and are not in parentheses!

@squirlmy 3 жыл бұрын

(Wow!(that was very silly)!)

@TheDavidlloydjones 3 жыл бұрын

@@squirlmy Thenkyew, thenkyew, layzun gennulmen out there in rayjoe lann. Keep those cards and letters coming... We especially appreciate that classic style, the bang between levels instead of TCP/IP.

@vincentkubicki1626 3 жыл бұрын

The Earth does not revolve around the Sun. This particular referential allows for the most elegant and simple mathematical representation.

@vincentkubicki1626 3 жыл бұрын

More seriously, the videos are amazing, and always at the exact level of complexity where you learn things, but it is still casual and you do not have to take notes or try to demonstrate things on the side.

@mikopiko 6 жыл бұрын

wow

@pitthepig 6 жыл бұрын

I expect something more of an edutainment channel in youtube than having simply a guy sitting in a chair and talking without any graphic support or any examples. This is lazy video production.

@hanniffydinn6019 6 жыл бұрын

You can write lisp in lisp very concisely, which is actual computing magic. It's so ahead of its time it's incredible....

@TheDuckofDoom. 6 жыл бұрын

I don't think that concision means what you think it means.

@mrdarky3377 5 жыл бұрын

MichaelKingsfordGray Yet clear enough for the determined mere mortals to comprehend and write.

@michaelcharlesthearchangel 6 жыл бұрын

I see Converse-Polish Notation, transverse operational listing, wright next to Reverse-Polish Notation. :.: (At the same time..) Non-linear code/language write nExt to Linear language/code. :: A Quantum Server for storing hyperGraphically compiled Holograms in Mass(ive) Data, ¹n² quantum inFormation; available for reCalling over and over aGain.