Trait InsertOpt

pub trait InsertOpt<K: Eq + Hash, V> {
    // Required method
    fn insert_opt(&mut self, key: impl Into<K>, value: Option<impl Into<V>>);
}

Required Methods

fn insert_opt(&mut self, key: impl Into<K>, value: Option<impl Into<V>>)

Insert an item only if it exists

Object Safety

This trait is not object safe.

Implementations on Foreign Types

impl<K: Eq + Hash, V> InsertOpt<K, V> for HashMap<K, V>

fn insert_opt(&mut self, key: impl Into<K>, value: Option<impl Into<V>>)

Implementors