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Move unreachable! to speaker notes (#2628)

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Nicole L
2025-02-26 12:22:13 -08:00
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src/control-flow-basics/macros.md
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@ -15,8 +15,6 @@ standard library includes an assortment of useful macros.
- `dbg!(expression)` logs the value of the expression and returns it. - `dbg!(expression)` logs the value of the expression and returns it.
- `todo!()` marks a bit of code as not-yet-implemented. If executed, it will - `todo!()` marks a bit of code as not-yet-implemented. If executed, it will
panic. panic.
- `unreachable!()` marks a bit of code as unreachable. If executed, it will
panic.
```rust,editable ```rust,editable
fn factorial(n: u32) -> u32 { fn factorial(n: u32) -> u32 {
@ -46,4 +44,19 @@ especially critical.
The course does not cover defining macros, but a later section will describe use The course does not cover defining macros, but a later section will describe use
of derive macros. of derive macros.
## More To Explore
There are a number of other useful macros provided by the standard library. Some
other examples you can share with students if they want to know more:
- [`assert!`] and related macros can be used to add assertions to your code.
These are used heavily in writing tests.
- [`unreachable!`] is used to mark a branch of control flow that should never be
hit.
- [`eprintln!`] allows you to print to stderr.
</details> </details>
[`assert!`]: https://doc.rust-lang.org/stable/std/macro.assert.html
[`unreachable!`]: https://doc.rust-lang.org/stable/std/macro.unreachable.html
[`eprintln!`]: https://doc.rust-lang.org/stable/std/macro.eprintln.html