| //@ run-pass |
| #![allow(non_camel_case_types)] |
| |
| |
| |
| trait to_str { |
| fn to_string_(&self) -> String; |
| } |
| impl to_str for isize { |
| fn to_string_(&self) -> String { self.to_string() } |
| } |
| impl to_str for String { |
| fn to_string_(&self) -> String { self.clone() } |
| } |
| impl to_str for () { |
| fn to_string_(&self) -> String { "()".to_string() } |
| } |
| |
| trait map<T> { |
| fn map<U, F>(&self, f: F) -> Vec<U> where F: FnMut(&T) -> U; |
| } |
| impl<T> map<T> for Vec<T> { |
| fn map<U, F>(&self, mut f: F) -> Vec<U> where F: FnMut(&T) -> U { |
| let mut r = Vec::new(); |
| for i in self { |
| r.push(f(i)); |
| } |
| r |
| } |
| } |
| |
| fn foo<U, T: map<U>>(x: T) -> Vec<String> { |
| x.map(|_e| "hi".to_string() ) |
| } |
| fn bar<U:to_str,T:map<U>>(x: T) -> Vec<String> { |
| x.map(|_e| _e.to_string_() ) |
| } |
| |
| pub fn main() { |
| assert_eq!(foo(vec![1]), ["hi".to_string()]); |
| assert_eq!(bar::<isize, Vec<isize> >(vec![4, 5]), ["4".to_string(), "5".to_string()]); |
| assert_eq!(bar::<String, Vec<String> >(vec!["x".to_string(), "y".to_string()]), |
| ["x".to_string(), "y".to_string()]); |
| assert_eq!(bar::<(), Vec<()>>(vec![()]), ["()".to_string()]); |
| } |
