// xfail-fast #[no_core]; use core; use core::{str, int, vec}; trait to_str { fn to_str() -> ~str; } impl int: to_str { fn to_str() -> ~str { int::str(self) } } impl ~[T]: to_str { fn to_str() -> ~str { ~"[" + str::connect(vec::map(self, |e| e.to_str() ), ~", ") + ~"]" } } fn main() { assert 1.to_str() == ~"1"; assert (~[2, 3, 4]).to_str() == ~"[2, 3, 4]"; fn indirect(x: T) -> ~str { x.to_str() + ~"!" } assert indirect(~[10, 20]) == ~"[10, 20]!"; fn indirect2(x: T) -> ~str { indirect(x) } assert indirect2(~[1]) == ~"[1]!"; }