"Parsing" is turning a stream of raw text or binary into some structured data types, i.e. a Rust type that your code can understand and use. This isn't the textbook definition of parsing, but damnit, this is my blog and my opinion. This tutorial is about nom, my favourite Rust parsing library. It uses a parser combinator approach: you start writing tiny parsers that match, say, a single number or a character. These become building blocks for larger parsers, that match, say, a date or a phone number. By combining many small parsers together, you can build a big parser that decodes a file or stream into nice Rust structs and enums. In this tutorial we'll use Nom to parse the input file to an Advent of Code puzzle.

Using async Rust libraries is usually easy. It's just like using normal Rust code, with a little async or .await here and there. But writing your own async libraries can be hard. The first time I tried this, I got really confused by arcane, esoteric syntax like T: ?Unpin and Pin<&mut Self>. I had never seen these types before, and I didn't understand what they were doing. Now that I understand them, I've written the explainer I wish I could have read back then. In this post, we're gonna learn

• What Futures are
• What self-referential types are
• Why they were unsafe
• How Pin/Unpin made them safe
• Using Pin/Unpin to write tricky nested futures

In part one, we defined a Grid trait and implemented it using 1D and 2D vectors. Benchmarks revealed that a 1D vector was a better choice than a nested 2D vector. In this post, we'll write a new implementation that uses arrays instead of Vec. This should be faster!

While making a raytracer in Rust, I needed an efficient way to store the pixels of a 2D image. In this post, we'll compare two different implementations of a 2D grid datatype, dipping our toes into data parallelism with Rayon and benchmarking with Criterion.