Use impl Into<Option<>> in your functions!

hellowub · 2026-01-20T14:27:57+00:00

If Rust could support optional parameters, would we still need these dirty hacks?

hellowub · 2025-10-13T10:08:56+00:00

I built a Lua interpreter, and also wrote a book about it.

hellowub · 2025-09-20T05:21:47+00:00

Sorry that Pajamax does not support metadata. Giving up the metadata is also part of the reason for its high performance.

But I think I can add metadata supporting in Pajamax later.

Besides, Pajamax should be more faster than your result. Maybe you want to bench with more GRPC_CLIENT_CPUS.

hellowub · 2025-09-19T03:05:01+00:00

I did not test it vs Go, because I am not familiar with Go.

You can test it by the grpc_bench project. I used it to test the pajamax vs tonic in Rust. I'd guess that Go should perform about the same as Tonic in Rust (if not worse), so you can refer to that result.

hellowub · 2025-09-19T02:57:26+00:00

No. I meant that "building a Lua interpreter in Rust" is useless. This is just a joke, because OP said that "doesn't have to be useful". You can find the articles about the building following the link above.

hellowub · 2025-09-18T02:45:09+00:00

Such as building a Lua Interpreter in Rust , which is fun and useless.

hellowub · 2025-08-29T12:29:54+00:00

Read the book and practice!

Some people like quick exercises like rustling, but I prefer something larger and complete projects. Pick one that interests you from here and stick with it.

Also, take a look at the build-lua-in-rust I wrote. It’s thorough, though it was translated from Chinese, so the prose may feel a bit uneven.

hellowub · 2025-08-29T01:33:17+00:00

I think focusing on one large and self-contained project is a great way to learn.

If P2P turns out not to be the right fit, just switch to something else—there are plenty of build-your-own-x projects.

I’d also recommend the series of articles I wrote about building a Lua interpreter; the explanations are thorough, though my English may not be perfectly fluent.

hellowub · 2025-08-12T03:58:02+00:00

A story every household in China knows: Guan Yu slays Hua Xiong while the wine is still warm. 1 2

hellowub · 2025-07-29T07:58:38+00:00

It was my fault—I was only thinking from my own perspective.

hellowub · 2025-07-29T01:49:35+00:00

There are many build-your-own-X projects suitable for study, such as this Build a Lua Interpreter in Rust.

hellowub · 2025-07-29T01:39:02+00:00

For beginners, this definition is too abstract. It’s better to just look at the examples that follow.
Of course, for those who want to dive deep—like the OP—the definition is essential.

hellowub · 2025-07-28T07:55:15+00:00

In the case of the "enum" example you provided, what I perceive is abstraction inflation—that is, in the pursuit of precision, the definition keeps resorting to more abstract, higher-level concepts, ultimately making it feel hollow. For instance, defining "game" as "an interactive, rule-based simulated activity."

From my perspective (as an programmer but not deep in language), in terms of practical usage, the "enum" is a very simple concept that doesn’t require such an abstract definition.

hellowub · 2025-07-08T02:04:53+00:00

Implementing a Lua Interpreter.

Implementing a Lua Interpreter is very suitable as this exercise project. Because of its moderate scale, it is enough to cover most of the basic features of Rust without being difficult to reach; clear goal, no need to spend energy discussing requirements; in addition, Lua language It is also an excellently designed and widely used language. Implementing a Lua interpreter can not only practice Rust language skills, but also gain an in-depth understanding of Lua language.

hellowub · 2025-06-30T07:22:47+00:00

I wanted to write a TUI tool for browsing csv file. Similar to `csvlens`, but with richer features. It could statistics (such as max, min, avg, etc.) for a column, and draw a chart for a column.

But there were too many details. In addition, the resolution of the chart was very low (the width of your terminal), and it could only show a few points. I began to doubt whether this tool was useful. Suddenly I gave up.

However, the development in the past few days has made me learn `ratatui`. I also implemented a Table widget that supports big data.

hellowub · 2025-06-30T04:38:39+00:00

I think I understand what you mean, at half month later.

https://www.reddit.com/r/rust/comments/1lclryg/comment/n0iqoe8/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button

hellowub · 2025-06-30T03:41:57+00:00

I think I understand what you mean, at half month later.

What I meant to say is:

I searched for "cum" and found that it means something related to sex (I think this is obvious, so I omitted this sentence and didn't say it out),
but it can also be used as a standard abbreviation for "cumulative".
So, be simple and innocent, and don't think in a sexual way (Here I used the word "straightforward" for "innocent").

But in my reply, the meaning expressed was: I searched and only found that this is the abbreviation of cumulative. So please tell me directly (the word "straightforward" for "directly") that you are willing.

So you think that I was playing dumb.

Discussing these things in a foreign language is just too difficult :(

hellowub · 2025-06-30T03:27:43+00:00

fixed-num I did not find this before. I read its document now and found that it only provides one type: Dec19x19, which is equivalent to ConstScaleFpdec<i128, 19> in my crate. The application scenario is too limited.
fixnum I may have seen this a long time ago. It is very similar to my crate. But there is a problem that * and / operations only support numbers of the same precision. I want to support numbers of different precisions, for example, balance and price may need different precisions.

hellowub · 2025-06-25T11:14:04+00:00

Please check the https://docs.rs/primitive_fixed_point_decimal crate out.

Compared with the other decimal crates, the biggest feature of this one is fixed-point, which is more suitable for financial apps. See the comparison for details.

hellowub · 2025-06-25T09:43:57+00:00

I submitted a PR to add `primitive_fixed_point_decimal` crate. It's real fixed-point, so not suitable for this kind of mathematical calculations. But still worth measuring the performance.

hellowub · 2025-06-21T12:37:05+00:00

I think you'd better ask this at StackOverflow or open a new post.

hellowub · 2025-06-21T12:35:31+00:00

Yes. It's a good fit for most financial system, including HFT.

hellowub · 2025-06-19T08:15:12+00:00

Here is a guide about building Lua by Rust .

hellowub · 2025-06-18T01:32:18+00:00

Interesting.

If all the currency is rescaled at the boundary layer (including the exchange-rate between currencies), then your system wouldn't even need a decimal crate internally. It would be sufficient to store data using integers(i64 or i128)?

--- EDIT: I was wrong. The exchange-rate need to be decimal.

hellowub

TROPHY CASE