Category: Programming
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A taxonomy of C++ types
You may have heard of things like fundamental types, built-in types, basic types, integral types, arithmetic types, and so on. But what do they all mean, if anything? In this post I’ll gradually build up the hierarchy of C++ types, eventually arriving at a big tree like in the following figure. But I promise we’ll…
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Using CoPilot-Like Tools is Not Pairing
Ever since the rise of LLM based tools like ChatGPT and CoPilot there have been quips made about how great it makes as a pairing partner. The joke is because these tools are passive and won’t trash your code, or disagree with your approach, or smell of…
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Rust 101 – 46: Exercises for module F (q1)
Coding up a linked list based on raw pointers in Rust. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async, Unsafe This section (Async): 42: Why unsafe?, 43: Meaning of unsafe, 44: Undefined behaviour, 45: Unsafe types, 46: Exercise 1 Links: Slides: Rust 101 – module F Exercises:…
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Rust 101 – 45: Unsafe types and examples
Looking through some of the types of code you will be working with if you’re doing unsafe Rust, and some of the unsafe types you might want to use. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async, Unsafe This section (Async): 42: Why unsafe?, 43: Meaning of…
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Rust 101 – 44: Undefined behaviour
If you write unsafe Rust, you need to reason about “undefined behaviour”. We talk through what that means, and try to develop an intuition about why we can’t predict how our program will behave if we don’t follow the rules. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects,…
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Rust 101 – 43: The two meanings of “unsafe” in Rust
The `unsafe` keyword in Rust means two things: “You must read the docs!” or “I promise I read the docs and followed the rules!”. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async, Unsafe This section (Async): 42: Why unsafe?, 43: Meaning of unsafe Links: Slides: Rust 101…
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Rust 101 – 42: Why do we need unsafe?
There is a special mode in Rust programs called unsafe – why do we need it? Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async, Unsafe This section (Async): 42: Why unsafe? Links: Slides: Rust 101 – module F Exercises: artificialworlds.net/presentations/rust-101/exercises/F-safe-unsafe/mod.html The course materials for this series are…
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Rust 101 – 41: Exercises for module E (q2b)
Writing a mini client to connect to our async Rust chat server. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async This section (Async): 34: What is async?, 35: Futures, 36: async/await, 37: Runtimes, 38: Exercise E1a, 39: Exercise E1b, 40: Exercise E2a, 41: Exercise E2b Links: Slides:…
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Rust 101 – 40: Exercises for module E (q2a)
Writing a little chat server in async Rust. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async This section (Async): 34: What is async?, 35: Futures, 36: async/await, 37: Runtimes, 38: Exercise E1a, 39: Exercise E1b, 40: Exercise E2a, 41: Exercise E2b Links: Slides: Rust 101 – module…
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Rust 101 – 39: Exercises for module E (q1b)
Writing a one-shot queue using async Rust, this time with a little less help. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async This section (Async): 34: What is async?, 35: Futures, 36: async/await, 37: Runtimes, 38: Exercise E1a, 39: Exercise E1b, 40: Exercise E2a, 41: Exercise E2b…
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Rust 101 – 38: Exercises for module E (q1a)
Writing our own multi-producer-single-consumer (MPSC) queue using async Rust. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async This section (Async): 34: What is async?, 35: Futures, 36: async/await, 37: Runtimes, 38: Exercise E1a, 39: Exercise E1b, 40: Exercise E2a, 41: Exercise E2b Links: Slides: Rust 101 –…
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Rust 101 – 37: Async runtimes
We talked about how Futures have poll methods, but who calls them? That is the job of the runtime. We talk about how to launch your async code and how to choose the right runtime, and then we have a very brief look at some Web frameworks that are based on async Rust. Series: Language…
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Rust 101 – 36: What async and await really do
Attempting to explain as slowly as possible what actually happens when the compiler finds an async function containing awaits: it writes a poll method for you to create something that implements Future. The generated poll method polls the Futures you asked to await, in order. The interesting bit is that this generated thing that implements…
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Rust 101 – 35: Futures
Exploring what a Future is in async Rust and how we could manually write code that polls futures. Normally, we avoid this manual work by using the `async` and `await` keywords, but looking into this helps us understand what those keywords really do. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and…
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Rust 101 – 34: What is async?
What async programming is and what it looks like in Rust. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async This section (Async): 34: What is async?, 35: Futures, 36: async/await, 37: Runtimes, 38: Exercise E1a, 39: Exercise E1b, 40: Exercise E2a, 41: Exercise E2b Links: Slides: Rust…
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Rust 101 – 33: Exercises for module D (q3)
Following through an exercise using a trait object with dynamic dispatch to choose different behaviour at runtime. Series: Language basics, More syntax, Traits and generics, Building applications, Concurrency and parallelism, Trait objects, Async This section (Trait objects): 28: Dynamic dispatch, 29: Object safety, 30: Patterns, 31: Exercise D1, 32: Exercise D2, 33: Exercise D3 Links:…
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The Perils of Multi-Phase Construction
I’ve never really been a fan of C#’s object initializer syntax. Yes, it’s a little more convenient to write but it has a big downside which is it forces you to make your types mutable by default. Okay, that’s a bit strong, it doesn’t force you to do an…
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The Perils of Multi-Phase Construction
I’ve never really been a fan of C#’s object initializer syntax. Yes, it’s a little more convenient to write but it has a big downside which is it forces you to make your types mutable by default. Okay, that’s a bit strong, it doesn’t force you to do an…
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Constantly Confusing: C++ const and constexpr pointer behaviour
A quick explanation of how const and constexpr work on pointers in C++So I was checking that my knowledge was correct when working on a Firefox bug.I made a quick C++ file with all the examples I know of how to use const and constexpr on pointers.As on…
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Working with PDF Highlight Annotations Programmatically
PDFs are the format of choice in academia, but extracting the information they contain is annoyingly hard.I’ve just started working on my degree’s final project. An academic project requires lots of research, which means reading lots of papers.Papers a…