rustlings/macros/macros3.rs

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2017-03-17 14:30:29 +00:00
// Make me compile, without taking the macro out of the module! Scroll down for hints :)
mod macros {
macro_rules! my_macro {
() => {
println!("Check out my macro!");
};
}
}
fn main() {
my_macro!();
}
2017-03-19 14:10:48 +00:00
// In order to use a macro outside of its module, you need to do something
// special to the module to lift the macro out into its parent.
2017-03-17 14:30:29 +00:00
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// The same trick also works on "extern crate" statements for crates that have
// exported macros, if you've seen any of those around.