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Formatter (#51)

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Enforce consistent formatting use `dprint`
This commit is contained in:
Luca Palmieri
2024-05-24 17:00:03 +02:00
committed by GitHub
parent 537118574b
commit 99591a715e
157 changed files with 1057 additions and 1044 deletions
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12
book/src/05_ticket_v2/09_error_trait.md
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@@ -2,8 +2,8 @@
## Error reporting
In the previous exercise you had to destructure the `InvalidTitle` variant to extract the error message and
pass it to the `panic!` macro.
In the previous exercise you had to destructure the `InvalidTitle` variant to extract the error message and
pass it to the `panic!` macro.\
This is a (rudimentary) example of **error reporting**: transforming an error type into a representation that can be
shown to a user, a service operator, or a developer.
@@ -13,7 +13,7 @@ That's why Rust provides the `std::error::Error` trait.
## The `Error` trait
There are no constraints on the type of the `Err` variant in a `Result`, but it's a good practice to use a type
There are no constraints on the type of the `Err` variant in a `Result`, but it's a good practice to use a type
that implements the `Error` trait.
`Error` is the cornerstone of Rust's error handling story:
@@ -31,7 +31,7 @@ implement `Debug` and `Display`.
We've already encountered the `Debug` trait in [a previous exercise](../04_traits/04_derive.md)—it's the trait used by
`assert_eq!` to display the values of the variables it's comparing when the assertion fails.
From a "mechanical" perspective, `Display` and `Debug` are identical—they encode how a type should be converted
From a "mechanical" perspective, `Display` and `Debug` are identical—they encode how a type should be converted
into a string-like representation:
```rust
@@ -46,8 +46,8 @@ pub trait Display {
}
```
The difference is in their *purpose*: `Display` returns a representation that's meant for "end-users",
while `Debug` provides a low-level representation that's more suitable to developers and service operators.
The difference is in their _purpose_: `Display` returns a representation that's meant for "end-users",
while `Debug` provides a low-level representation that's more suitable to developers and service operators.\
That's why `Debug` can be automatically implemented using the `#[derive(Debug)]` attribute, while `Display`
**requires** a manual implementation.