1,117 karma · joined November 17, 2022
I disagree. The code you wrote is a collaboration with the model you used. To frame it this way, you are taking credit for the work the model did on your behalf. There is a difference between I wrote this code entirely by myself and I wrote the code with a partner. For me, it is analogous to the author of the score of an opera taking credit for the libretto because they gave the libretto author the rough narrative arc. If you didn't do it yourself, it isn't yours.
I generally prefer integrated works or at least ones that clearly acknowledge the collaboration and give proper credit.
Moreover, I view optimization as an anti-pattern in general, especially for a low level language. It is better to directly write the optimal solution and not be dependent on the compiler. If there is a real hotspot that you have identified through profiling and you don't know how to optimize it, then you can run the hotspot through an optimizing compiler and copy what it does.
What you then realize is that it is possible to generate quality machine code much faster than LLVM and using far fewer resources. I believe both that LLVM has been holding back compiler evolution and that it is close to if not already at peak popularity. As LLMs improve, the need for tighter feedback loops will necessitate moving off the bloat of LLVM. Moreover, for all of the magic of LLVMs optimization passes, it does very little to prevent the user from writing incorrect code. I believe we will demand more from a compiler backend than LLVM can ever deliver.
The main selling point of LLVM is that you gain access to all of the targets, but this is for me a weak point in its favor. Firstly, one can write a quality self hosting compiler with O(20) instructions. Adding new backends should be trivial. Moreover, the more you are thinking about cross platform portability, the more you are worrying about hypothetical problems as well as the problems of people other than yourself. Get your compiler working well first on your machine and then worry about other machines.
I take a very different view about the trajectory of languages given the current trends in software development. The more people rely upon agentic coding processes, the more they will demand faster compilation which will increasingly become a significant bottleneck on product velocity. The faster the llms get, the more important it is for the tools they use to be fast. Right now, I still think we are in an uncanny valley where llms are still slow enough that slow tooling does not seem that bad, but this is likely to change. People will no longer be satisfied asking their agent to make a change and come back in a minute or an hour. They will expect the result nearly instantaneously. C++ (and rust) compile times are too slow for the agent to iterate in the human reaction window so I believe that one of two things will happen over the next few years: llm progress will stall out or c++ and rust will nosedive in popularity.
Personally though, I think the distinctive choices are a boon. You are never confused about what language you are writing because Lua code is so obviously Lua. There is value in this. Once you have written enough Lua, your mind easily switches in and out of Lua mode. Javascript, on the other hand, is filled with poor semantic decisions which for me, cancel out any benefits from syntactic familiarity.
More importantly, Lua has a crucial feature that Javascript lacks: tail call optimization. There are programs that I can easily write in Lua, in spite of its syntactic verbosity, that I cannot write in Javascript because of this limitation. Perhaps this particular JS implementation has tco, but I doubt it reading the release notes.
I have learned as much from Lua as I have Forth (SmallTalk doesn't interest me) and my programming skill has increased significantly since I switched to it as my primary language. Lua is the only lightweight language that I am aware of with TCO. In my programs, I have banned the use of loops. This is a liberation that is not possible in JS or even c, where TCO cannot be relied upon.
In particular, Lua is an exceptional language for writing compilers. Compilers are inherently recursive and thus languages lacking TCO are a poor fit (even if people have been valiantly forcing that square peg through a round hole for all this time).
Having said all that, perhaps as a scripting language for Redis, JS is a better fit. For me though Lua is clearly better than JS on many different dimensions and I don't appreciate the needless denigration of Lua, especially from someone as influential as you.
When one looks at languages that use LLVM as a backend, there is one consistent property: slow compilation. Because of how widespread LLVM is, we often seem to accept this as a fact of life and that we are forced to make a choice between fast runtime code and a fast compiler. This is a false choice.
Look at two somewhat recent languages that use LLVM as a backend: zig and rust. The former has acknowledged that LLVM is an albatross and are in the process of writing their own backends to escape its limitations. The latter is burdened with ridiculous compilation times that will never get meaningfully better so long as they avoid writing their own backend.
Personally, I find LLVM a quite disempowering technology. It creates the impression that its complexity is necessary for quality and performance and makes people dependent on it instead of developing their own skills. This is not entirely dissimilar to another hot technology with almost the same initials.
In the OP examples, instead of optimization, what I would prefer is a separate analysis tool that reports what optimizations are possible and a compiler that makes it easy to write both high level and machine code as necessary. Now instead of the compiler opaquely rewriting your code for you, it helps guide you into writing optimal code at the source level. This, for me, leads to a better equilibrium where you are able to express your intent at a high level and then, as needed, you can perform lower level optimizations in a transparent and deterministic way.
For me, the big value of existing optimizing compilers is that I can use them to figure out what instructions might be optimal for my use case and then I can directly write those instructions where the highest performance is needed. But I do not need to subject myself to the slow compilation times (which compounds as the compiler repeatedly reoptimizes the same function thousands of times during development -- a cost that is repeated with every single compilation of the file) nor the possibility that the optimizer breaks my code in an opaque way that I won't notice until something bad and inscrutable happens at runtime.
I have been studying compiler design for several years and I have found that writing a simple parser by hand is the best way to go most of the time. There is a process to it: You start with a "Hello, world!" program and you parse it character by character with no separate lexer. You ensure that at each step in your parser, you make an unambiguous decision at each character and never backtrack. The decision may be that you need to enter a disambiguation function that also only moves forward. If the grammar gets in the way of conserving this property, change the grammar not the parser design.
If you follow that high level algorithm, you will end up with a parser with performance linear in the number of characters which is asymptotically as well as you can hope to do. It is both easy and simple to implement (provided you have solid programming fundamentals) and no caching is needed for efficiency.
Deliberate backtracking in a compiler is an evil that should be avoided at all costs. It is potentially injecting exponentially poor performance into a developer's primary feedback loop which is a theft of their time for which they have little to no recourse.
Personally, I think it is wrong to inflict your experiments on other people and when you pull the rug out from underneath say, well, we told you it was unstable, you should't have depended on us in the first place.
I don't even understand what zig is supposed to be. Matklad seems to think it is a machine level language: https://lobste.rs/s/ntruuu/lobsters_interview_with_matklad. This contrasts with the official language landing page: Zig is a general-purpose programming language and toolchain for maintaining robust, optimal and reusable software. These two definitions are mutually incompatible. Moreover, zig is clearly not a general purpose language because there are plenty of programming problems where manual memory management is neither needed nor desirable.
All of this confusion is manifest in zig's instability and bloated standard library. Indeed a huge standard library is incompatible with the claims of simplicity and generality they frequently make. Async is not a feature that can be implemented universally without adding overhead and indirection because of the fundamental differences in capabilities exposed by the various platforms. Again, they are promising a silver bullet even though their prior attempt, in which they publicly proclaimed function coloring to be solved, has been abandoned. Why would we trust them to get it right a second time?
There are a very small number of assembly primitives that every platform provides that are necessary to implement a compiler. Load/store/mov/inc/jeq/jump and perhaps a few others. Luajit implements its parser in pure assembly and I am not aware of an important platform that luajit runs on that zig goes. I do the vast majority of my programming in lua and _never_ run into bugs in the interpreter. I truly cannot think of a single problem that I think zig would solve better than luajit. Even if that did exist, I could embed the zig code in my lua file and use lua to drive the zig compiler and then call into the specialized code using the lua ffi. But the vast majority of code does not need to be optimized to the level of machine code where it is worth putting up with all of the other headaches that adopting zig will create.
The hype around zig is truly reaching llm levels of disconnection from reality. Again, to believe in zig, one has to believe it will magically develop capacities that it does not presently have and for which there is no plan to actually execute besides vague plans of just wait.
For me, today this split is almost always a mistake. Having everything in one file is superior the vast majority of the time. Search is easy and it is completely clear where everything is in the project. Most projects written by a single individual will be fewer than 10K lines which many compilers can clean compile in less than one second. And I have reached the stage of my programming journey where I would rather not ever work on sprawling hundred K + line projects written by dozens or hundreds of authors.
If the single file gets too unwieldy, splitting it in my opinion usually makes the problem worse. It is like cleaning up by sweeping everything under the rug. The fact that the file got so unwieldy was a symptom that the design got confused and the single file no longer is coherent. Splitting it rarely makes it more coherent.
To make things more concrete and simple. For me the following structure is strictly better (in lua like the op)
foo.lua:
local bar = function() print "bar" end
return function()
print "foo"
bar()
end
compared to bar.lua:
return function() print "bar" end
foo.lua:
local bar = require "bar"
return function()
print "foo"
bar()
end
In the latter, I now both have to keep track of what and where bar is and switch files to see its contents or rely on fancy editors tricks. With the former, I can use vim and if I want to remind myself of the definition bar, it is as easy as `?bar =`. I end up with the same code either way, but it is much easier to view in a single file and I can take advantage of lua's scoping rules to keep module details local to the module even from other modules defined in the same file.For me, this makes it much easier to focus and I am liberated from the problem of where submodules are located in the project. I can also recursively keep subdividing the problem into smaller and smaller subproblems that do not escape their context so that even though the file might grow large, the actual functions tend to be reasonably small.
That this is also the easiest way to distribute code is a nice bonus.