// run-pass #![allow(dead_code)] #![allow(unused_variables)] #![allow(unconditional_recursion)] // Check that we do not ICE when compiling this // macro, which reuses the expression `$id` #![feature(box_patterns)] struct Foo { a: isize } pub enum Bar { Bar1, Bar2(isize, Box<Bar>), } impl Foo { fn elaborate_stm(&mut self, s: Box<Bar>) -> Box<Bar> { macro_rules! declare { ($id:expr, $rest:expr) => ({ self.check_id($id); Box::new(Bar::Bar2($id, $rest)) }) } match s { box Bar::Bar2(id, rest) => declare!(id, self.elaborate_stm(rest)), _ => panic!() } } fn check_id(&mut self, s: isize) { panic!() } } pub fn main() { }