This crate provides GettersByType
derive macro for structs, which implements a getter method for each type they contain.
The generated methods start with the prefix get_fields_
and end with a transcription of the type they refer.
Example using GettersByType
:
```rust
struct Foo { first: i32, second: i32, third: i32, }
let object = Foo { first: 6, second: 12, third: 24 };
// Let's sum all the i32 fields with a fold expression: asserteq!(object.getfields_i32().iter().fold(0, |acc, x| **x + acc), 42); ```
As you notice, the getter methods return an array containing references to all the fields of the same type.
In that example, the return type of the method get_fields_i32
would be [&i32; 3]
.
This crate also provides a mut
version GettersMutByType
which also adds a mut version for those methods.
In this case, the generated methods start with the prefix get_mut_fields_
instead.
Example using GettersMutByType
:
```rust
struct Foo { first: Updater, second: Updater, ... onehundredth: Updater, }
impl Updater { fn update(&mut self) {...} }
let mut object = Foo::new();
// Let's update all the Updater fields for updater in object.getmutfieldsupdater().itermut() { updater.update(); } ```
In this example, the return type of the method get_mut_fields_updater
would be [&mut Updater; 3]
.
There is no dynamic memory allocation happening within the getter methods, as they just return a fixed array with references.
There isn't also unsafe code being generated.
For more information, check the documentation page.
With Cargo, you can add this line to your Cargo.toml:
toml
[dependencies]
getters-by-type = "*"
This currently works with primitive types, and many other referencial and genecic types, such as &str
or Vec
, but there are cases that are not completely covered, like the trait objects. Want to contribute? Pull requests are always welcome. Because this is my first work with procedural macros, I guess things can improve a fair lot under the hood, so there should be a few low hanging fruits already. Let's go for them!
MIT