rust/tests/ui/macros/macro-at-most-once-rep-2018.rs

43 lines
1.1 KiB
Rust

// Tests that `?` is a Kleene op and not a macro separator in the 2018 edition.
//@ edition:2018
macro_rules! foo {
($(a)?) => {};
}
// The Kleene op `?` does not admit a separator before it.
macro_rules! baz {
($(a),?) => {}; //~ERROR the `?` macro repetition operator
}
macro_rules! barplus {
($(a)?+) => {}; // ok. matches "a+" and "+"
}
macro_rules! barstar {
($(a)?*) => {}; // ok. matches "a*" and "*"
}
pub fn main() {
foo!();
foo!(a);
foo!(a?); //~ ERROR no rules expected `?`
foo!(a?a); //~ ERROR no rules expected `?`
foo!(a?a?a); //~ ERROR no rules expected `?`
barplus!(); //~ERROR unexpected end of macro invocation
barplus!(a); //~ERROR unexpected end of macro invocation
barplus!(a?); //~ ERROR no rules expected `?`
barplus!(a?a); //~ ERROR no rules expected `?`
barplus!(a+);
barplus!(+);
barstar!(); //~ERROR unexpected end of macro invocation
barstar!(a); //~ERROR unexpected end of macro invocation
barstar!(a?); //~ ERROR no rules expected `?`
barstar!(a?a); //~ ERROR no rules expected `?`
barstar!(a*);
barstar!(*);
}