// 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 the token `?` foo!(a?a); //~ ERROR no rules expected the token `?` foo!(a?a?a); //~ ERROR no rules expected the token `?` barplus!(); //~ERROR unexpected end of macro invocation barplus!(a); //~ERROR unexpected end of macro invocation barplus!(a?); //~ ERROR no rules expected the token `?` barplus!(a?a); //~ ERROR no rules expected the token `?` barplus!(a+); barplus!(+); barstar!(); //~ERROR unexpected end of macro invocation barstar!(a); //~ERROR unexpected end of macro invocation barstar!(a?); //~ ERROR no rules expected the token `?` barstar!(a?a); //~ ERROR no rules expected the token `?` barstar!(a*); barstar!(*); }