Trait std::ops::IndexExperimental

pub trait Index<Index, Result> {
    fn index(&'a self, index: &Index) -> &'a Result;
}

The Index trait is used to specify the functionality of indexing operations like arr[idx] when used in an immutable context.

Example

A trivial implementation of Index. When Foo[Foo] happens, it ends up calling index, and therefore, main prints Indexing!.

#[deriving(Copy)] struct Foo; impl Index<Foo, Foo> for Foo { fn index<'a>(&'a self, _index: &Foo) -> &'a Foo { println!("Indexing!"); self } } fn main() { Foo[Foo]; }

#[deriving(Copy)]
struct Foo;

impl Index<Foo, Foo> for Foo {
    fn index<'a>(&'a self, _index: &Foo) -> &'a Foo {
        println!("Indexing!");
        self
    }
}

fn main() {
    Foo[Foo];
}

Required Methods

fn index(&'a self, index: &Index) -> &'a Result

The method for the indexing (Foo[Bar]) operation

Implementors

• impl<T> Index<uint, T> for [T]
• impl<K: Hash<S> + Eq, Q: ?Sized, V, S, H: Hasher<S>> Index<Q, V> for HashMap<K, V, H> where Q: BorrowFrom<K> + Hash<S> + Eq
• impl<K: Hash<S> + Eq, Q: ?Sized, V, S, H: Hasher<S>> Index<Q, V> for HashMap<K, V, H> where Q: BorrowFrom<K> + Hash<S> + Eq
• impl Index<uint, bool> for Bitv
• impl<K: Ord, Q, V> Index<Q, V> for BTreeMap<K, V>
• impl<A> Index<uint, A> for RingBuf<A>
• impl<T> Index<uint, T> for Vec<T>
• impl<V> Index<uint, V> for VecMap<V>