diff options
Diffstat (limited to 'src/test/ui/unboxed-closures/unboxed-closures-fnmut-as-fn.rs')
-rw-r--r-- | src/test/ui/unboxed-closures/unboxed-closures-fnmut-as-fn.rs | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/src/test/ui/unboxed-closures/unboxed-closures-fnmut-as-fn.rs b/src/test/ui/unboxed-closures/unboxed-closures-fnmut-as-fn.rs new file mode 100644 index 000000000..867e5fb1d --- /dev/null +++ b/src/test/ui/unboxed-closures/unboxed-closures-fnmut-as-fn.rs @@ -0,0 +1,29 @@ +// Checks that the Fn trait hierarchy rules do not permit +// Fn to be used where FnMut is implemented. + +#![feature(fn_traits, unboxed_closures)] + +use std::ops::{Fn,FnMut,FnOnce}; + +struct S; + +impl FnMut<(isize,)> for S { + extern "rust-call" fn call_mut(&mut self, (x,): (isize,)) -> isize { + x * x + } +} + +impl FnOnce<(isize,)> for S { + type Output = isize; + + extern "rust-call" fn call_once(mut self, args: (isize,)) -> isize { self.call_mut(args) } +} + +fn call_it<F:Fn(isize)->isize>(f: &F, x: isize) -> isize { + f.call((x,)) +} + +fn main() { + let x = call_it(&S, 22); + //~^ ERROR E0277 +} |