std::unordered_map<Key,T,Hash,KeyEqual,Allocator>::at

Returns a reference to the mapped value of the element with specified key. If no such element exists, an exception of type std::out_of_range is thrown.

# Declarations

T& at( const Key& key );

(since C++11)

const T& at( const Key& key ) const;

(since C++11)

template< class K >
T& at( const K& x );

(since C++26)

template< class K >
const T& at( const K& x ) const;

(since C++26)

# Parameters

# Return value

A reference to the mapped value of the requested element.

# Notes

Feature-test macro Value Std Feature __cpp_lib_associative_heterogeneous_insertion 202311L (C++26) Heterogeneous overloads for the remaining member functions in ordered and unordered associative containers. (3,4)

# Example

This section is incompleteReason: no example

# See also