rustHow to set default value in Rust struct

Setting a default value in a Rust struct is a simple process. To do this, you need to use the Default trait. This trait allows you to set a default value for a field in a struct.

Example code

use std::default::Default;

#[derive(Default)]
struct MyStruct {
    field1: i32,
    field2: String,
}

fn main() {
    let my_struct = MyStruct::default();
    println!("{}", my_struct.field1);
    println!("{}", my_struct.field2);
}

Output example

0

Code explanation

1. use std::default::Default;: This imports the Default trait from the standard library.
2. #[derive(Default)]: This is a Rust attribute that tells the compiler to automatically implement the Default trait for the MyStruct struct.
3. let my_struct = MyStruct::default();: This creates an instance of MyStruct and sets the fields to their default values.
4. println!("{}", my_struct.field1);: This prints the value of field1 which is set to 0 by the Default trait.
5. println!("{}", my_struct.field2);: This prints the value of field2 which is set to an empty string by the Default trait.

Helpful links

• The Rust Programming Language - Default Trait
• The Rust Programming Language - Derive Attribute

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