unstable book: default_free_fn · rust-lang/rust@ebb8722 (original) (raw)

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	1	+# `default_free_fn`
	2	+
	3	+The tracking issue for this feature is: [#73014]
	4	+
	5	+[#73014]: https://github.com/rust-lang/rust/issues/73014
	6	+
	7	+------------------------
	8	+
	9	+Adds a free `default()` function to the `std::default` module. This function
	10	+just forwards to [`Default::default()`], but may remove repetition of the word
	11	+"default" from the call site.
	12	+
	13	+Here is an example:
	14	+
	15	+```rust
	16	+#![feature(default_free_fn)]
	17	+use std::default::default;
	18	+
	19	+#[derive(Default)]
	20	+struct AppConfig {
	21	+foo: FooConfig,
	22	+bar: BarConfig,
	23	+}
	24	+
	25	+#[derive(Default)]
	26	+struct FooConfig {
	27	+foo: i32,
	28	+}
	29	+
	30	+#[derive(Default)]
	31	+struct BarConfig {
	32	+bar: f32,
	33	+baz: u8,
	34	+}
	35	+
	36	+fn main() {
	37	+let options = AppConfig {
	38	+foo: default(),
	39	+bar: BarConfig {
	40	+bar: 10.1,
	41	+..default()
	42	+ },
	43	+ };
	44	+}
	45	+```