Crate short_default 

Short Default

Avoid writing tedious Default implementations by using a simple default! macro instead.

Usage

use short_default::default;

// Define a new struct with default values
default! {
    struct Config {
        version: (u64, u64, u64) = (0, 1, 0),
        // This default value will be inferred via
        // authors: Default::default(),
        authors: Vec<String>,
    }
}

// Use the default implementation
let config = Config::default();

assert_eq!(config.version, (0, 1, 0));
assert_eq!(config.authors.len(), 0);

Side-by-Side Comparison

Short Default

use short_default::default;
default! {
    struct SomeOptions {
        foo: i32 = 10,
        bar: f32 = 5.0,
        baz: String = "bazzz".to_string(),
        qux: Option<bool> = Some(false),
        corge: Vec<i32>,
    }
}

Traditional Approach

struct SomeOptions {
    foo: i32,
    bar: f32,
    baz: String,
    qux: Option<bool>,
    corge: Vec<i32>,
}
impl Default for SomeOptions {
    fn default() -> Self {
        Self {
            foo: 10,
            bar: 5.0,
            baz: "bazz".to_string(),
            qux: Some(false),
            corge: Vec::default(),
        }
    }
}

Supported Features

The definition of the struct preceding the equal sign for each field is parsed conventionally and identically returned. This means that any regular syntax which such as field attributes, generics, etc. works as well.

Macros

default

See the crate-level documentation