trait vec_monad<A> {
- fn bind<B>(&self, f: |&A| -> Vec<B> ) -> Vec<B> ;
+ fn bind<B, F>(&self, f: F ) -> Vec<B> where F: FnMut(&A) -> Vec<B> ;
}
impl<A> vec_monad<A> for Vec<A> {
- fn bind<B>(&self, f: |&A| -> Vec<B> ) -> Vec<B> {
+ fn bind<B, F>(&self, mut f: F) -> Vec<B> where F: FnMut(&A) -> Vec<B> {
let mut r = Vec::new();
for elt in self.iter() {
r.extend(f(elt).into_iter());
}
trait option_monad<A> {
- fn bind<B>(&self, f: |&A| -> Option<B>) -> Option<B>;
+ fn bind<B, F>(&self, f: F) -> Option<B> where F: FnOnce(&A) -> Option<B>;
}
impl<A> option_monad<A> for Option<A> {
- fn bind<B>(&self, f: |&A| -> Option<B>) -> Option<B> {
+ fn bind<B, F>(&self, f: F) -> Option<B> where F: FnOnce(&A) -> Option<B> {
match *self {
Some(ref a) => { f(a) }
None => { None }