Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
std::flat_map::at(3)	      C++ Standard Libary	  std::flat_map::at(3)

NAME
       std::flat_map::at - std::flat_map::at

Synopsis
	  T& at( const Key& key	);	       (1) (since C++23)
	  const	T& at( const Key& key )	const; (2) (since C++23)
	  template< class K >		       (3) (since C++23)
	  T& at( const K& x );
	  template< class K >		       (4) (since C++23)
	  const	T& at( const K&	x ) const;

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

	  1,2) The key is equivalent to	key.
	  3,4)	The  key  compares equivalent to the value x. The reference to
       the mapped value
	  is obtained as if by expression this->find(x)->second.
	  The expression this->find(x) must be well-formed and	have  well-de-
       fined behavior,
	  otherwise the	behavior is undefined.
	  These	overloads participate in overload resolution only if the qual-
       ified-id
	  Compare::is_transparent is valid and denotes a type. It allows call-
       ing this	function
	  without constructing an instance of Key.

Parameters
	  key -	the key	of the element to find
	  x    - a value of any	type that can be transparently compared	with a
       key

Return value
	  A reference to the mapped value of the requested element.

Exceptions
	  1,2) std::out_of_range if the	container does	not  have  an  element
       with the	specified
	  key.
	  3,4)	std::out_of_range if the container does	not have the specified
       element,	that
	  is, if find(x) == end() is true.

Complexity
	  Logarithmic in the size of the container.

Example
	   This	section	is incomplete
	   Reason: no example

See also
	  operator[] access or insert specified	element
		     (public member function)

Category:
	    * Todo no example

http://cppreference.com		  2024.06.10		  std::flat_map::at(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::flat_map::at&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help