std::use_facet

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Defined in header <locale>

template< class Facet >
const Facet& use_facet( const std::locale& loc)

Obtains a reference to a facet implemented by loc.

Contents

[edit] Parameters

loc - the locale object to query

[edit] Return value

Returns a reference the facet. The reference returned by this function is valid as long as any std::locale object exists that implements Facet.

[edit] Exceptions

std::bad_cast if std::has_facet<Facet>(loc) == false.

[edit] Example

Display the 3-letter currency name used by the user's preferred locale

#include <iostream>
#include <locale>
int main()
{
    std::locale loc = std::locale(""); // user's preferred locale
    std::cout << "Your currency string is "
              << std::use_facet<std::moneypunct<char, true>>(loc).curr_symbol() << '\n';

Output:

Your currency string is USD

[edit] See also

locale
set of polymorphic facets that encapsulate cultural differences
(class)
has_facet
checks if a locale implements a specific facet
(function template)