Trait HashMapExt 

pub trait HashMapExt<K, V> {
    // Required method
    fn try_insert_ext(
        &mut self,
        k: K,
        v: V,
    ) -> Option<(V, OccupiedEntry<'_, K, V>)>;
}

Extension trait for HashMap<K, V>.

Required Methods

fn try_insert_ext(&mut self, k: K, v: V) -> Option<(V, OccupiedEntry<'_, K, V>)>

Like insert, but if the insertion fails then it returns the value that it attempted to insert, as well as an OccupiedEntry containing the other value that was found.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl<K: Hash + Eq, V, S: BuildHasher> HashMapExt<K, V> for HashMap<K, V, S>

fn try_insert_ext(&mut self, k: K, v: V) -> Option<(V, OccupiedEntry<'_, K, V>)>

Implementors