Implement “From” trait…

Basic implementation of From trait to create “MyStruct” from type: i32

struct MyStruct{
    word: String,
    number: i32
}

impl From<i32> for MyStruct{
    fn from(num: i32) -> MyStruct {
        MyStruct {
            word: "notset".to_string(),
            number: num
        }
    }
    
}

fn main() {
    let m = MyStruct::from(25);
    let n: MyStruct = 30.into();
    println!("Struct m: word={}, number={}.", m.word, m.number);
    println!("Struct n: word={}, number={}.", n.word, n.number);
}

Notice that I can run 30.into above. I didn’t add that explicitly.

Output of above:

Struct m: word=notset, number=25.
Struct n: word=notset, number=30.

Implement "From" Trait

Learning Rust

Implement “From” trait…

Output of above:

See also