import a::*; import b::baz; mod a { impl foo for uint { fn plus() -> int { self as int + 20 } } } mod b { impl baz for str { fn plus() -> int { 200 } } } impl util for uint { fn str() -> str { uint::str(self) } fn times(f: fn(uint)) { let c = 0u; while c < self { f(c); c += 1u; } } } impl util for [T] { fn length() -> uint { vec::len(self) } fn iter(f: fn(T)) { for x in self { f(x); } } fn map(f: fn(T) -> U) -> [U] { let r = []; for elt in self { r += [f(elt)]; } r } } fn main() { impl foo for int { fn plus() -> int { self + 10 } } assert 10.plus() == 20; assert 10u.plus() == 30; assert "hi".plus() == 200; assert [1].length().str() == "1"; assert [3, 4].map({|a| a + 4})[0] == 7; assert [3, 4].map::({|a| a as uint + 4u})[0] == 7u; let x = 0u; 10u.times {|_n| x += 2u;} assert x == 20u; }