4 ms·

Chez scheme is just as dynamic as python and is about as fast as C# running on mono IIRC. My scheme was probably worse than my C# was when I did project Euler t

by bjoli 7y ago

Chez scheme is just as dynamic as python and is about as fast as C# running on mono IIRC. My scheme was probably worse than my C# was when I did project Euler though. Chez does unboxed integer arithmetic (but not floats) and does not have to do any OO-like dispatch, and is also probably one of the best language implementations there are.

tluyben2 7y ago
A nice show of Chez Scheme speed is Idris 2. Edwin is very impressed with the performance; it is very fast. And imho it is a lovely language with, as you rightfully say, one of the best implementations out there. Extremely portable (cpu/OS). And quite readable too.
username90 7y ago
C# running on mono is in my experience 10 times slower than equivalent C++ even for simple things like adding numbers in an array.
- bjoli 7y ago
  That story of mine is old, but I have some newer anecdata: porting all my old project Euler solutions to SBCL and getting help by some better lispers than me to optimize it made SBCL come out close, but almost universally slower than Chez if someone really wants I can see if I find the code on any of my external HDDs. A number quoted is that SBCL preforms roughly on par with, but slightly slower than, java. For what it is worth, the computer benchmarks game confirms that: https://benchmarksgame-team.pages.debian.net/benchmarksgame/fastest/lisp.html https://benchmarksgame-team.pages.debian.net/benchmarksgame/... That was with optimize level 3, which burns on (car 1), and then you might as well use C, but the language at least allows for those speeds.
  - omaranto 7y ago
    Ooh! I don't think I've ever seen someone claim Chez Scheme produced faster code than SBCL before. That's interesting.
    - bjoli 7y ago
      It is hard to claim, because there are hardly any benchmarks. I just had the opportunity to move between the implementations and found chez to be faster for the kind of things I was doing, which was numerical stuff and loops. SBCL is also an amazing project, and lately the GC story has gotten better IIRC.
  - igouy 7y ago
    So will Racket become super super fast ? "… Racket CS available, a beta version of the Racket on Chez Scheme implementation." https://download.racket-lang.org/v7.4.html https://download.racket-lang.org/v7.4.html
    - bjoli 7y ago
      Probably not, but the code is a hell of a lot cleaner! I looked through it and thought that even I could work on it. The new macro expander is even possible to follow :)
peatmoss 7y ago
It’s hard to find a Scheme implementaron that isn’t significantly faster than Python... all while being at least as dynamic and more expressive. I think a lot of CS students had their brains melted by tough classes where Scheme was the vehicle. Thus, you have a population of users that either are anti-evangelists because they have PTSD, or you have evangelists who exist on a plane above the lumpenproletariat like me, which can contribute to the false notion that Scheme is intrinsically esoteric. I never got a formal CS education, so I don’t have PTSD from Scheme. Also, I am not a super brain, so I guess I haven’t felt compelled to become expert at the hard concepts that Scheme enables. People fixate on the S-expression syntax (“all those parentheses!”; counter argument “way fewer commas!”). But I think the real issue for Scheme is the lack of libraries that do hard things for “normals” like me. If I’m strictly honest, I’m more productive in Python than Scheme. This is not because Python is easier. It’s because the Python community has attracted the CS grads who grokked enough of the hard stuff to make libraries that abstract away stuff. There’s no reason people can’t write Scheme like they write Python. That is, people don’t need to do all the possible stuff in Scheme all the time. Truthfully, Scheme is at least as easy as Python. Scheme just needs more smart normals writing libraries for mediocre normals like me for Scheme to become popular. Maybe take a domain approach. I feel like adapting R’s tidyverse to Chez is an easy target. Scheme could be the data scientist’s goto. Maybe show people how easy it is to build self-contained serverless apps in the cloud. If there were a Scheme community that earnestly tackled any domain with the idea of making it accessible to practitioners within the domain, I think it could get real traction. And it would be fast. Much faster than Python.
jerf 7y ago
"Chez scheme is just as dynamic as python" Is it? Python is really, really dynamic, which contributes to its slowness. You can directly change an instance's __class__ attribute. You can add properties to classes dynamically, changing how fundamentals of how attributes get looked up at run time. You can write a new class, using a new metaclass, and then set an existing instance to the new class. A great deal of why Python is so slow is that it is really too dynamic. A language doesn't really want to be "as dynamic as Python".
- pjmlp 7y ago
  Nothing that Common Lisp or Smalltalk aren't capable of doing as well, and they have quite capable JITs. As an example, Smalltalk becomes: message completely replaces one object representation by another one.
- bjoli 7y ago
  Chez lacks a built in OOP system, but there is nothing prohibiting you from adding something like CLOS which does all python does and more (much faster than python). Most modern lisp compilers do a lot of different things to make CLOS fast, though, prefilling caches and all that for you. Not only that, you can connect to a running program and redefine it while it is running.
  - jerf 7y ago
    "Chez lacks a built in OOP system," In that case, the answer is actually no to my question. Yes, of course you could program in that level of dynamicness, because you could in any language, but it will then slow you down. No sensible CLOS would be as dynamic as Python. Like I said, in a lot of ways, you don't want to be as dynamic as Python, and I advise against language advocates seeing the phrase "Python is more dynamic than your language" as a cue to jump up and start insisting that they are just as dynamic as Python. Even in hindsight, I'd say the level of dynamicness in Python was a mistake. You don't need it to have a nice, usable, dynamic language, but it has been a ball & chain around its legs in terms of performance for decades. To be clear, this isn't a criticism of dynamic languages as a concept. I have criticisms, but these aren't it. This is a criticism of Python specifically. A dynamic language can be pretty nice with, let's say, two or three layers of dynamicness, but Python has four or five. If you follow the full process that Python has to go through to resolve "x.y", including all possible points where you might have done something to affect the result, it's crazy overkill. In Guido's defense, when he was writing it way back when, that wasn't clear. There wasn't a lot of highly-relevant prior art to look at for that style language.
kragen 7y ago
Scheme is relentlessly monomorphic, and most implementations don't provide much reflection, preferring compile-time macros. (I don't know what Chez’s reflection facilities are like; can you do the equivalent of def __getitem__ or x.__setattr__ = y?) These attributes make Scheme much easier than Python to implement efficiently. My experience is that simple programs usually take about twice as much code in Scheme. This is related to the polymorphism thing, but also I think Python supports imperative programming better. Python is built around autogrowing hash tables (“dicts”) and autogrowing arrays (“lists”); standard Scheme provides neither, preferring alists and cons lists.
- bjoli 7y ago
  In guile I would do (define-method (get (lst <list>) (n <integer>)) (list-ref lst n)) in chez I would probably use chez soop, which is hideously underdocumented and probably bitrotten by now, or any of the other object systems available. It would of course slow things down since I doubt chez optimizes that so you get runtime dispatch. SBCL however has an amazing object systems that does all of python's Oop with pretty good speed. You are right that python is better at imperative programming, but that is also very much a matter fo taste. I always get a sour feeling in my mouth when using python because it is almost exclusively about mutability. (hashtables are a part of r6rs, btw. Not very pleasant to use since: (hashtable-ref h key default-value))

by bjoli 7y ago

tluyben2 7y ago

A nice show of Chez Scheme speed is Idris 2. Edwin is very impressed with the performance; it is very fast. And imho it is a lovely language with, as you rightfully say, one of the best implementations out there. Extremely portable (cpu/OS). And quite readable too.

username90 7y ago

C# running on mono is in my experience 10 times slower than equivalent C++ even for simple things like adding numbers in an array.

bjoli 7y ago
That story of mine is old, but I have some newer anecdata: porting all my old project Euler solutions to SBCL and getting help by some better lispers than me to optimize it made SBCL come out close, but almost universally slower than Chez if someone really wants I can see if I find the code on any of my external HDDs. A number quoted is that SBCL preforms roughly on par with, but slightly slower than, java. For what it is worth, the computer benchmarks game confirms that: https://benchmarksgame-team.pages.debian.net/benchmarksgame/fastest/lisp.html https://benchmarksgame-team.pages.debian.net/benchmarksgame/... That was with optimize level 3, which burns on (car 1), and then you might as well use C, but the language at least allows for those speeds.
- omaranto 7y ago
  Ooh! I don't think I've ever seen someone claim Chez Scheme produced faster code than SBCL before. That's interesting.
  - bjoli 7y ago
    It is hard to claim, because there are hardly any benchmarks. I just had the opportunity to move between the implementations and found chez to be faster for the kind of things I was doing, which was numerical stuff and loops. SBCL is also an amazing project, and lately the GC story has gotten better IIRC.
- igouy 7y ago
  So will Racket become super super fast ? "… Racket CS available, a beta version of the Racket on Chez Scheme implementation." https://download.racket-lang.org/v7.4.html https://download.racket-lang.org/v7.4.html
  - bjoli 7y ago
    Probably not, but the code is a hell of a lot cleaner! I looked through it and thought that even I could work on it. The new macro expander is even possible to follow :)

peatmoss 7y ago

It’s hard to find a Scheme implementaron that isn’t significantly faster than Python... all while being at least as dynamic and more expressive. I think a lot of CS students had their brains melted by tough classes where Scheme was the vehicle. Thus, you have a population of users that either are anti-evangelists because they have PTSD, or you have evangelists who exist on a plane above the lumpenproletariat like me, which can contribute to the false notion that Scheme is intrinsically esoteric. I never got a formal CS education, so I don’t have PTSD from Scheme. Also, I am not a super brain, so I guess I haven’t felt compelled to become expert at the hard concepts that Scheme enables. People fixate on the S-expression syntax (“all those parentheses!”; counter argument “way fewer commas!”). But I think the real issue for Scheme is the lack of libraries that do hard things for “normals” like me. If I’m strictly honest, I’m more productive in Python than Scheme. This is not because Python is easier. It’s because the Python community has attracted the CS grads who grokked enough of the hard stuff to make libraries that abstract away stuff. There’s no reason people can’t write Scheme like they write Python. That is, people don’t need to do all the possible stuff in Scheme all the time. Truthfully, Scheme is at least as easy as Python. Scheme just needs more smart normals writing libraries for mediocre normals like me for Scheme to become popular. Maybe take a domain approach. I feel like adapting R’s tidyverse to Chez is an easy target. Scheme could be the data scientist’s goto. Maybe show people how easy it is to build self-contained serverless apps in the cloud. If there were a Scheme community that earnestly tackled any domain with the idea of making it accessible to practitioners within the domain, I think it could get real traction. And it would be fast. Much faster than Python.

jerf 7y ago

"Chez scheme is just as dynamic as python" Is it? Python is really, really dynamic, which contributes to its slowness. You can directly change an instance's __class__ attribute. You can add properties to classes dynamically, changing how fundamentals of how attributes get looked up at run time. You can write a new class, using a new metaclass, and then set an existing instance to the new class. A great deal of why Python is so slow is that it is really too dynamic. A language doesn't really want to be "as dynamic as Python".

pjmlp 7y ago
Nothing that Common Lisp or Smalltalk aren't capable of doing as well, and they have quite capable JITs. As an example, Smalltalk becomes: message completely replaces one object representation by another one.
bjoli 7y ago
Chez lacks a built in OOP system, but there is nothing prohibiting you from adding something like CLOS which does all python does and more (much faster than python). Most modern lisp compilers do a lot of different things to make CLOS fast, though, prefilling caches and all that for you. Not only that, you can connect to a running program and redefine it while it is running.
- jerf 7y ago
  "Chez lacks a built in OOP system," In that case, the answer is actually no to my question. Yes, of course you could program in that level of dynamicness, because you could in any language, but it will then slow you down. No sensible CLOS would be as dynamic as Python. Like I said, in a lot of ways, you don't want to be as dynamic as Python, and I advise against language advocates seeing the phrase "Python is more dynamic than your language" as a cue to jump up and start insisting that they are just as dynamic as Python. Even in hindsight, I'd say the level of dynamicness in Python was a mistake. You don't need it to have a nice, usable, dynamic language, but it has been a ball & chain around its legs in terms of performance for decades. To be clear, this isn't a criticism of dynamic languages as a concept. I have criticisms, but these aren't it. This is a criticism of Python specifically. A dynamic language can be pretty nice with, let's say, two or three layers of dynamicness, but Python has four or five. If you follow the full process that Python has to go through to resolve "x.y", including all possible points where you might have done something to affect the result, it's crazy overkill. In Guido's defense, when he was writing it way back when, that wasn't clear. There wasn't a lot of highly-relevant prior art to look at for that style language.

kragen 7y ago

Scheme is relentlessly monomorphic, and most implementations don't provide much reflection, preferring compile-time macros. (I don't know what Chez’s reflection facilities are like; can you do the equivalent of def __getitem__ or x.__setattr__ = y?) These attributes make Scheme much easier than Python to implement efficiently. My experience is that simple programs usually take about twice as much code in Scheme. This is related to the polymorphism thing, but also I think Python supports imperative programming better. Python is built around autogrowing hash tables (“dicts”) and autogrowing arrays (“lists”); standard Scheme provides neither, preferring alists and cons lists.

bjoli 7y ago
In guile I would do (define-method (get (lst <list>) (n <integer>)) (list-ref lst n)) in chez I would probably use chez soop, which is hideously underdocumented and probably bitrotten by now, or any of the other object systems available. It would of course slow things down since I doubt chez optimizes that so you get runtime dispatch. SBCL however has an amazing object systems that does all of python's Oop with pretty good speed. You are right that python is better at imperative programming, but that is also very much a matter fo taste. I always get a sour feeling in my mouth when using python because it is almost exclusively about mutability. (hashtables are a part of r6rs, btw. Not very pleasant to use since: (hashtable-ref h key default-value))