Macro count_macro::count

count!() { /* proc-macro */ }

Count without wrapping (panic if counter exceeds usize). Every instance of _int_ and _int_countername_ will be replaced with the counter value and then the counter will be increased.

Examples

Ident to literal

use count_macro::count;

let a = count!(vec![_int_, _int_, _int_]);
assert_eq!(a, vec![0, 1, 2]);

Ident to ident

use count_macro::count;

count! {
    let a_int_ = "Hello";
    let a_int_ = "World";
}

assert_eq!(a0, "Hello");
assert_eq!(a1, "World");

In macro

use count_macro::count;

macro_rules! my_macro {
    ($($v:expr),*) => {
        count!{
            $(
                let _ = $v; // Ignoring $v

                println!("{}", _int_);
            )*
        }
    };
}

my_macro!('@', '@', '@', '@'); // Will print from 0 to 3

Multiple counters

use count_macro::count;

// With two different counters
// _int_ does not increment _int_name_
count! {
    let a_int_ = _int_name_;
    let a_int_ = _int_name_;
    let a_int_ = _int_name_;
}

assert_eq!(a0, 0);
assert_eq!(a1, 1);
assert_eq!(a2, 2);