macro_rules! column { () => { ... }; }
A macro which expands to the column number on which it was invoked.
The expanded expression has type u32
, 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.
let current_col = column!(); println!("defined on column: {}", current_col);
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Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/macro.column.html