Print type of variable

• type_name

• type_name_of_val

• Sometimes during development, during the exploration of Rust it is useful to print the type of a varible.

• This is one way to do it.

• It will be added to the stanard library as type_name_of_val.

fn main() {
    let an_integer = 42;
    print_type(&an_integer);

    let a_float = 4.2;
    print_type(&a_float);

    let an_str = "Hello";
    print_type(&an_str);

    let a_string = String::from("World");
    print_type(&a_string);

    let a_vector = vec![3, 4, 5];
    print_type(&a_vector);

    // An iterator
    let readdir = std::path::Path::new(".").read_dir().unwrap();
    print_type(&readdir);
}

fn print_type<T>(_: &T) {
    println!("{:?}", std::any::type_name::<T>());
}

"i32"
"f64"
"&str"
"alloc::string::String"
"alloc::vec::Vec<i32>"
"std::fs::ReadDir"