I've got the following source file, with various permutations to the parameter on line 2: ``` fn main() { io::println(~"foo" + ~"foo"); } ``` - `~"foo" + ~"foo"`: compiles as expected; outputs `foofoo` - `"foo" + ~"foo"`: fails to compile: error: binary operation + cannot be applied to type `&static/str` - `~"foo" + "foo"`: compiles as expected; outputs `foofoo` - `"foo" + "foo"`: fails to compile: error: binary operation + cannot be applied to type `&static/str` - `~"foo" + @"foo"`: compiles as expected; outputs `foofoo` - `@"foo" + ~"foo"`: fails to compile: error: binary operation + cannot be applied to type `@str` - `@"foo" + @"foo"`: fails to compile: error: binary operation + cannot be applied to type `@str` This is f96a2a2ca1 running on Mac OS 10.8.2.