std::column!

macro_rules! column { () => ({ /* compiler built-in */ }) }

A macro which expands to the column number on which it was invoked.

The expanded expression has type usize, and the returned column is not the invocation of the column!() macro itself, but rather the first macro invocation leading up to the invocation of the column!() macro.

Example

fn main() { let current_col = column!(); println!("defined on column: {}", current_col); }

let current_col = column!();
println!("defined on column: {}", current_col);