| # Std library types | |
| The `std` library provides many custom types which expands drastically on | |
| the `primitives`. Some of these include: | |
| * growable `String`s like: `"hello world"` | |
| * growable vectors: `[1, 2, 3]` | |
| * optional types: `Option<i32>` | |
| * error handling types: `Result<i32, i32>` | |
| * heap allocated pointers: `Box<i32>` | |
| ### See also: | |
| [primitives] and [the std library][std] | |
| [primitives]: primitives.md | |
| [std]: https://doc.rust-lang.org/std/ |