# Notes for AI agents
## Project overview
`rust-petname` is a Rust crate (library + CLI binary) for generating human-readable random names like _remarkably-striking-cricket_. It is a reimplementation of Dustin Kirkland's [petname](https://github.com/dustinkirkland/petname) with additional features.
The crate is `no_std` (with `extern crate alloc`). Feature flags:
- `default-rng` – enables `rand`'s default thread-local RNG
- `default-words` – embeds the built-in word lists via the `petnames!` macro
- `macros` – enables the `petnames!` proc macro (in the `petname-macros` subcrate)
## Key types
- `Petnames<'a>` – holds three word lists (adjectives, adverbs, nouns) as `Cow<'a, [&'a str]>`. Implements `Generator`.
- `Alliterations<'a>` – a `BTreeMap<char, Petnames<'a>>` grouping words by first letter for alliterative generation. Implements `Generator`.
- `Generator` – trait with a single required method `generate_into`. Object-safe: takes `&mut dyn rand::Rng`.
- `Namer<'a, G>` – a config struct (word count, separator, reference to a `Generator`). Created by `Petnames::namer` or `Alliterations::namer`. Has `generate_into` and `iter` methods. No trait import needed to use it.
`Namer::generate_into` writes into a caller-supplied `String` buffer (more efficient). `Namer::iter` yields owned `String`s via `core::iter::from_fn`.
## Testing
Run tests with `cargo hack --feature-powerset test` to cover all feature combinations. CI uses `cargo hack` for this purpose.
## Writing style
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