# enum2str
[](https://github.com/matthewjberger/enum2str)
[](https://crates.io/crates/enum2str)
[](https://docs.rs/enum2str)
enum2str is a rust derive macro that creates a Display impl for enums.
This is useful for strongly typing composable sets of strings.
## Usage
Add this to your `Cargo.toml`:
```toml
enum2str = "0.1.11"
```
Example:
```rust
use enum2str::EnumStr;
#[derive(EnumStr)]
enum Object {
Generic(String),
#[enum2str("Color: {}. Shape: {}.")]
Complex(Color, Shape),
// Variant fields can be ignored
#[enum2str("Material")]
Material(Color),
}
#[derive(EnumStr)]
enum Color {
Green,
#[enum2str("Burgundy")]
Red,
Blue {
_hue: u8,
},
#[enum2str("Custom Color")]
Custom {
_red: u8,
_green: u8,
_blue: u8,
},
#[enum2str("Unique - {label}_{id}")]
Unique {
id: u8,
label: String,
},
}
#[derive(EnumStr)]
enum Shape {
#[enum2str("Circle with radius: {}")]
Circle(u8),
}
#[test]
fn color_variant_names() {
assert_eq!(
Color::variant_names(),
vec![
"Green".to_string(),
"Red".to_string(),
"Blue".to_string(),
"Custom".to_string(),
"Unique".to_string(),
]
);
}
#[test]
fn unit_to_string() {
assert_eq!(Color::Green.to_string(), "Green");
}
#[test]
fn unit_override_string() {
assert_eq!(Color::Red.to_string(), "Burgundy");
}
#[test]
fn unnamed_to_string() {
assert_eq!(Object::Generic("Hello!".to_string()).to_string(), "Hello!");
}
#[test]
fn nested_to_string() {
assert_eq!(
Object::Complex(Color::Green, Shape::Circle(2)).to_string(),
"Color: Green. Shape: Circle with radius: 2."
);
}
#[test]
fn unit_template() {
assert_eq!(Color::Green.template(), "Green");
}
#[test]
fn unit_override_template() {
assert_eq!(Color::Red.template(), "Burgundy");
}
#[test]
fn unnamed_template() {
assert_eq!(Shape::Circle(2).template(), "Circle with radius: {}");
}
#[test]
fn nested_template() {
assert_eq!(
Object::Complex(Color::Green, Shape::Circle(2)).template(),
"Color: {}. Shape: {}."
);
}
#[test]
fn unit_args() {
assert_eq!(Color::Green.arguments().len(), 0);
}
#[test]
fn unnamed_args() {
assert_eq!(
Object::Generic("Hello!".to_string()).arguments(),
vec!["Hello!".to_string()]
);
}
#[test]
fn complex_args() {
assert_eq!(
Object::Complex(Color::Green, Shape::Circle(2)).arguments(),
vec!["Green", "Circle with radius: 2"],
);
}
#[test]
fn plain_to_string() {
assert_eq!(Color::Blue { _hue: 3 }.to_string(), "Blue");
}
#[test]
fn unique_to_string() {
assert_eq!(
Color::Unique {
label: "unique_color".to_string(),
id: 3
}
.to_string(),
"Unique - unique_color_3",
);
}
#[test]
fn custom_args() {
assert_eq!(
Color::Unique {
label: "unique_color".to_string(),
id: 3
}
.arguments()
.len(),
2
);
}
```