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#![deny(unused_macro_rules)]
// To make sure we are not hitting this
#![deny(unused_macros)]
macro_rules! num {
(one) => { 1 };
// Most simple (and common) case
(two) => { compile_error!("foo"); };
// Some nested use
(two_) => { foo(compile_error!("foo")); };
(three) => { 3 };
(four) => { 4 }; //~ ERROR: rule of macro
}
const _NUM: u8 = num!(one) + num!(three);
// compile_error not used as a macro invocation
macro_rules! num2 {
(one) => { 1 };
// Only identifier present
(two) => { fn compile_error() {} }; //~ ERROR: rule of macro
// Only identifier and bang present
(two_) => { compile_error! }; //~ ERROR: rule of macro
(three) => { 3 };
}
const _NUM2: u8 = num2!(one) + num2!(three);
fn main() {}
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