For a language that announced itself (and raised a lot of money on the premise of) claiming to be "a Python superset", this does not sound like a huge achievement.
In all fairness, their website now reads: "Mojo is a pythonic language for blazing-fast CPU+GPU execution without CUDA. Optionally use it with MAX for insanely fast AI inference."
So I suppose now is just a compiled language with superficially similar syntax and completely different semantics to Python?
I think it was pretty clear immediately that running python code was a far away goal. There was a lot more talk about lifetimes and ownership semantics than details about Python interop. Mojo is more like: Can we take the learnings of Swift and Rust and solve the usability and compile time issues, while building on MLIR to target arbitrary architectures efficiently (and call it a Python superset to raise VC money).
That said, the upside is huge. If they can get to a point where Python programmers that need to add speed learn Mojo, because it feels more familiar and interops more easily, rather than C/CPP that would be huge. And it's a much lower bar than superset of python.
It marketed itself explicitly as a "Python superset", which could allow Python programmers to avoid learning a second language and write performant code.
I'd argue that I am not sure what kind of Python programmer is capable of learning things like comptime, borrow checking, generics but would struggle with different looking syntax. So to me this seemed like a deliberate misrepresentation of the actual challenges to generate hype and marketing.
Which fair enough, I suppose this is how things work. But it should be _fair_ to point out the obvious too.
Absolutely. The public sales pitch did not match the reality. This is what I meant with the "Claim to be Ṕython to get VC money" point.
To first order, today every programmer starts out as a Python programmer. Python is _the_ teaching language now. The jump from Python to C/Cpp is pretty drastic, I don't think that it's absurd that learning Mojo concepts step by step coming from Python is simpler than learning C. Not syntactically but conceptually.
Maybe young generations have some issue learning polyglot programming, I guess.
While I agree using Mojo is much preferable to writing C or C++ native extensions, back on my day people learned to program in K&R C or C++ ARM in high school, kids around 12 years old, hardly something pretty drastic.
Many famous Speccy and C64 titles, written in Assembly, were written by bedroom coders between the ages of 14 and 16 years old, getting some pocket money writing them on the UK scene.
Get hold of Retro Gamer magazine for some of their stories.
I've tried learning C a couple times and given up because the curve is too steep to be worth the climb. It's not even the language itself, it's the inherited weight of half a century's worth of cruft. I can't spend weeks fighting with compiler nonsense, header files and #include. Screw it, I'll just use Go instead.
I'm learning Rust and Zig in the hope that I'll never have to write a line of C in my career.
Geez, what a comment. C is much much more simpler than Rust. You’re not supposed to be spending weeks fighting includes or compiler errors, that means you’re have some very basic misconceptions about the language.
Just read K&R “The C programming language” book.
It’s fairly small and it’s a very good introduction to C.
C syntactically is straight forward, but conceptually may be harder than Rust. You’re exposed to the bare computer (memory management, etc) far more than with a GC language or even Rust arguably, at least for simple programs.
Towards deployment is even harder. You can very easily end up writing exploitable, unsafe code in C.
If I were a Python programmer with little knowledge about how a computer works, I’d much prefer Go or Rust (in that order) to C.
This is true, but when you get something wrong related to the memory model in C, it just says "segfault". Whereas in Rust it will give you a whole explanation for what went wrong and helpful suggestions on how to fix it. Or at the very least it will tell you where the problem is. This is the difference between "simple" and "easy".
That applies only if you take "memory model" to mean modeling the effects of concurrent accesses in multithreaded programs.
But the term could also be used more generally to include stuff like pointer provenance, Rust's "stacked borrows" etc.
In that case, Rust is more complicated than C-as-specified. But C-in-reality is much more complicated, e.g. see https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2263.htm
The model you're referring to, a Memory Ordering Model, is literally the same model as Rust's. The "exception" is an ordering nobody knows how to implement which Rust just doesn't pretend to offer - a distinction which makes no difference.
I do sympathize with the parent: The language itself might not be that difficult but you also have to factor in the entire ecosystem. What's the modern way to a build a GUI application in C? What's the recommended way to build a CLI, short of writing your own arg parser? How do you handle Unicode? How do you manage dependencies, short of vendoring them? Etc.
Errors too. When, inevitably, you make mistakes the C might just compile despite being nonsense, or you might get incomprehensible diagnostics. Rust went out of its way to deliver great results here.
I am not arguing about how good or easy it is to use C in production, I’m merely stating that parent complaints about weeks of insolvable errors and issues with includes screams that he needs to read some good resource like book, because he is definitely misunderstanding something important.
THe thing is, if one is an expert it is incredibly difficult to understand the beginner perspective. Here is one attempt:
C is simpler than Rust, but C is also _much_ simpler than Python. If I solve a problem in Python I have a good standard library of data types, and I use concepts like classes, iterators, generators, closures, etc... constantly. So if I move to Rust, I have access to the similar high-level tools, I just have to learn a few additional concepts for ressource management.
In comaprison, C looks a lot more alien from that perspective. Even starting with including library code from elsewhere.
I think one of the "Python superset" promises was that any particular dev wouldn't need to learn all of that at once. There could exist a ramp between Python and "fast python" that is more gradual than the old ways of dropping into C, and more seamless than importing and learning the various numpy/numba/polars libraries.
FWIW generics are already a thing in pure Python as soon as you add type annotations, which is fast becoming the default (perhaps not the least because LLMs also seem to prefer it).
I suppose if you accept the innocent-looking "#"+"#"=="##" then your example kind of algebraically follows. Next it's time to define what exp("#") is :)
* does different things depending on the types of the operands, which is Python's strong typing at work, not Perlesque weak typing. Repeating a string is a useful thing to be able to do, and this is a natural choice of syntax for it. The same thing works for lists: [1]*3 == [1, 1, 1].
It does unfortunately mean that sometimes `*` will work (and produce an incorrect result) rather than immediately failing loudly with a clear error message in the context in which it's actually intended to be numerical.
More broadly this is the same argument as whether overloading `+` for strings is a bad idea or not, and the associated points, e.g. the fact that this makes it non-commutative - the same all applies to `*` as well, and to lists as much as strings. At least Python is consistent here.
Although there is one particular aspect that is IMO just bad design: the way `x += y` and `x = y` work. To remind, for lists these are not equivalent to `x = x + y` and `x = x y` - instead of creating a new list, they mutate the existing one in place, so all the references observe the change. This is very surprising and inconsistent with the same operators for numbers, or indeed for strings and tuples.
The real unique selling point of Mojo is "CPU+GPU execution without CUDA", specifically, you write code that looks like code without worrying about distinctions like kernels and device functions and different ways of writing code that runs on GPU vs. code that runs on CPU, and mojo compiles it to those things.
While much has changed since then, the architecture is effectively the same. Julia's native CUDA support simply boils down to compiling via the LLVM .ptx backend (Julia always generates LLVM IR, and the CUDA infrastructure "simply" retargets LLVM to .ptx, generates the binary, and then wraps that binary into a function which Julia calls), so it's really just a matter of the performance difference between the code generated by the LLVM .ptx backend vs the NVCC compiler.
> For a language that announced itself (and raised a lot of money on the premise of)
claiming to be "a Python superset", this does not sound like a huge achievement
I feel like that depends quite a lot on what exactly is in the non-subset part of the language. Being able to use a library from the superset in the subset requires being able to translate the features into something that can run in the subset, so if the superset is doing a lot of interesting things at runtime, that isn't necessarily going to be trivial.
(I have no idea exactly what features Mojo provides beyond what's already in Python, so maybe it's not much of an achievement in this case, but my point is that this has less to do with just being a superset but about what exactly the extra stuff is, so I'm not sure I buy the argument that the marketing you mention of enough to conclude that this isn't much of an achievement.)
I've written this somewhere else before, Modular did not raise $130m to build a programming language, nobody does that.
They raised that much money to revolutionize AI infrastructure, of which a language is just a subset. You should definitely check some of the things they've put together, they're amazing
Yes. They are revolutionizing AI infrastructure but I guess a lot of world is just babbling about AI, but not every developer needs to worry about AI.
And so his improvements in mojo and now calling mojo code from python just make a lot more net positive to the community than being, some other Ai infrastructure company.
So I do wish a lot of good luck to mojo. I have heard that mojo isn't open source but it has plans to do so. I'd like to try it once if its as fast / even a little slower than rust and comparable to understanding as python.
Agreed, Modular is walking a very fine line, and they're doing so by trading on the reputation of Chris Lattner.
On the one had, as the other poster noted, no one raises $100M+ for a programming language; programming languages have no ROI that would justify that kind of money. So to get it, they had to tell VCs a story about how they're going to revolutionize AI. It can't just be "python superset with MLIR". That's not a $100M story.
On the other hand, they need to appeal to the dev community. For devs, they want open source, they want integration with their tools, they don't want to be locked into a IP-encumbered ecosystem that tries to lock them in.
That's where the tension is. To raise money you need to pretend you're the next Oracle, but to get dev buy-in you have to promise you're not the next Oracle.
So the line they've decided to walk is "We will be closed for now while figure out the tech. Then later once we have money coming in to make the VCs happy, we can try to make good on our promise to be open."
That last part is the thing people are having trouble believing. Because the story always goes: "While we had the best intentions to be open and free, that ultimately came secondary to our investors' goal of making money. Because our continued existence depends on more money, we have decided to abandon our goal of being open and free."
And that's what makes these VC-funded language plays so fraught for devs. Spend the time to learn this thing which may never even live up to its promises? Most people won't, and I think the Darklang group found that out pretty decisively.
I don't think investors look at what makes a net positive to the community when making large investments like in Modular. I was calling out the part of the post that said Modular raised a lot of Money to develop Mojo, that isn't entirely true as just creating a language isn't enough reason to invest $130m into a company, no matter how much net-positivity the language would bring.
It was never going to have Python semantics and be fast. Python isn't slow because of a lack of effort or money, it's slow because of all the things happening in the interpreter.
> Further, we decided that the right long-term goal for Mojo is to adopt the syntax of Python (that is, to make Mojo compatible with existing Python programs) and to embrace the CPython implementation for long-tail ecosystem support
In all fairness, their website now reads: "Mojo is a pythonic language for blazing-fast CPU+GPU execution without CUDA. Optionally use it with MAX for insanely fast AI inference."
So I suppose now is just a compiled language with superficially similar syntax and completely different semantics to Python?