Struct Update Syntax with ..

Snippet

Struct Update Syntax with ..

The struct update syntax allows creating a new struct instance while copying most fields from an existing one. Fields not explicitly set take their values from the source struct, reducing boilerplate when working with similar configurations.

snippet.rs
rust
#[derive(Default, Debug)]
struct Config {
    timeout: u32,
    max_retries: u32,
    debug_mode: bool,
}
 
fn main() {
    let default_cfg = Config::default();
    let custom_cfg = Config {
        timeout: 30,
        ..default_cfg
    };
    println!("{:?}", custom_cfg);
}

Breakdown

..default_cfg

Copies all remaining fields from default_cfg that aren't explicitly set

timeout: 30,

Only timeout is changed; other fields come from default_cfg

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Struct Update Syntax with ..

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