/// Returns `true` if the set contains a value.
///
/// The value may be any borrowed form of the set's value type,
/// but the ordering on the borrowed form *must* match the
/// ordering on the value type.
///
/// # Examples
///
/// ```
/// use bumpalo::Bump;
/// use arena_collections::{MultiSetMut, SortedSet};
///
/// let b = Bump::new();
/// let mut set = MultiSetMut::new_in(&b);
/// set.insert(1);
/// let set = SortedSet::from(set);
/// assert!(set.contains(&1));
/// ```
Returns `true` if the set contains a value.
The value may be any borrowed form of the set's value type,
but the ordering on the borrowed form *must* match the
ordering on the value type.
Returns ` true ` if the set contains a value . The value may be any borrowed form of the set ' s value type but the ordering on the borrowed form * must * match the ordering on the value type .
pub fn contains<Q: ?Sized>(&self, value: &Q) -> bool
    where
        T: Borrow<Q>,
        Q: Ord,
    {
        self.list.contains_key(value)
    }
pub fn contains < Q : ? Sized > ( & self , value : & Q ) -> bool where T : Borrow < Q > , Q : Ord , { self . list . contains_key ( value ) }
Returns `true` if the set contains a value.
Returns ` true ` if the set contains a value .
&self
value
&Q
examples
```
use bumpalo::Bump;
use arena_collections::{MultiSetMut, SortedSet}.

let b = Bump::new();
let mut set = MultiSetMut::new_in(&b);
set.insert(1);
let set = SortedSet::from(set);
assert!(set.contains(&1));
```
` ` ` use bumpalo :: Bump ; use arena_collections :: { MultiSetMut SortedSet } . let b = Bump :: new () ; let mut set = MultiSetMut :: new_in ( &b ) ; set . insert ( 1 ) ; let set = SortedSet :: from ( set ) ; assert! ( set . contains ( &1 )) ; ` ` `