default_free_fn - The Rust Unstable Book

# `default_free_fn`

The tracking issue for this feature is: #73014

Adds a free `default()` function to the `std::default` module. This function just forwards to `Default::default()`, but may remove repetition of the word "default" from the call site.

Here is an example:

    #![feature(default_free_fn)]
    use std::default::default;

    #[derive(Default)]
    struct AppConfig {
        foo: FooConfig,
        bar: BarConfig,
    }

    #[derive(Default)]
    struct FooConfig {
        foo: i32,
    }

    #[derive(Default)]
    struct BarConfig {
        bar: f32,
        baz: u8,
    }

    fn main() {
        let options = AppConfig {
            foo: default(),
            bar: BarConfig {
                bar: 10.1,
                ..default()
            },
        };
    }