macro_rules! line { () => { ... }; }
A macro which expands to the line number on which it was invoked.
The expanded expression has type u32
, and the returned line is not the invocation of the line!()
macro itself, but rather the first macro invocation leading up to the invocation of the line!()
macro.
let current_line = line!(); println!("defined on line: {}", current_line);
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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.line.html