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Comment by geofft | Hacker News Reader

Tangentially - do you know how fast her compiler was compared to the compiled-language implementations? I have a vague sense that for many applications, interpreted languages are totally fine and reaching for a compiled language is premature optimization, but I'm curious how it actually holds up for a compiler, which is more computationally heavy than your average web app or CLI.

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No I don't know how fast her compiler was. This also isn't a good setup for comparing language performance, since all the test programs were small and there was no incentive to make your compiler fast. Many groups probably used O(n^2) algorithms in their compiler and differences in algorithm choice would probably add too much noise to get a good performance signal.

That aside, speaking off the cuff totally separately from my post, I'm extremely dissatisfied with the performance of current compilers. The fastest compilers written by performance-oriented programmers can be way faster than ones you generally encounter. See luajit and Jonathan Blow's 50k+ loc/second compilers and the kind of things they do for performance. One example of a compiler task it's really difficult to do quickly in a language like Python/Ruby is non-regex parsing, I've written recursive descent parsers in Ruby and compiled languages and the Ruby ones were 1-2 orders of magnitude slower, non-JIT dynamic languages are really bad at tight loops like that.

> I'm extremely dissatisfied with the performance of current compilers. The fastest compilers written by performance-oriented programmers can be way faster than ones you generally encounter. See luajit and Jonathan Blow's 50k+ loc/second compilers and the kind of things they do for performance.

Lua and Jai are lot less complex than say C++: sure, LLVM isn't necessarily built to be the fastest compiler in existence, but I don't think it's fair to compare it to compilers for much simpler languages and bemoan its relative slowness.

I wrote the python compiler. It's very slow. With the optimizations it's probably something on the order of O(n^3) or O(n^4). One of the test cases took seconds to compile. I made no effort to optimize the compiler speed.

Yep, the takeaway for me was that the Python project required far less code, but we're not sure how fast it ran. Further below, the author states the inputs were so small it didn't matter. What if it did? Would the Python solution still be viable?

0.5x with metaprogramming vs 0.7x without in Scala, isn't "far less". This also matches my experience - Scala is pretty on par with Python in terms of code length. It gets a tiny hit from being statically typed, but then makes up for it by having richer stdlib and powerful type-level abstractions.

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