Tag
6 posts
In languages without sum types, the visitor pattern exists to add operations to a type hierarchy. Rust's enums and match usually make it unnecessary, with a few exceptions.
Rust forbids adding inherent methods to foreign types, but a trait you define can. Extension traits are how itertools, futures and tokio add methods to the standard library.
A tuple struct with one field costs nothing at runtime and stops you passing a user id where an order id belongs. Learn construction, derives, Deref pitfalls and the orphan rule workaround.
Implement undo and redo in Rust with the command pattern: commands as an enum, execute and undo methods, history stacks, merging, and a text editor example.
A repository hides the database behind a trait. See when that helps (testing, swapping stores) and when it only adds indirection, with a concrete trait, an SQLx impl and an in-memory fake.
Rust match is exhaustive: the compiler checks every case. Learn literals, ranges, guards, bindings, tuple, struct and slice patterns with working examples.