src/test/compile-fail/missing-do.rs

// Regression test for issue #2783

fn foo(f: fn()) { f() }

fn main() {
    ~"" || 42; //~ ERROR binary operation || cannot be applied to type `~str`
    foo || {}; //~ ERROR binary operation || cannot be applied to type `fn(fn&())`
    //~^ NOTE did you forget the 'do' keyword for the call?
}