std::experimental::ranges::dangling, std::experimental::ranges::safe_iterator_t

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template < CopyConstructible T >

class dangling {
public :
    dangling( ) requires DefaultConstructible<T> ( ) ;
    dangling(T t) ;
    T get_unsafe( ) const ;

} ;
(ranges TS)
template < Range R >

using safe_iterator_t = std::conditional_t < std::is_lvalue_reference <R> :: value,
ranges::iterator_t <R>,

ranges::dangling < ranges::iterator_t <R>> ;
(ranges TS)

The class template dangling is a simple wrapper around an object to indicate that the wrapped object may be dangling, that is, it refers to another object whose lifetime may have ended.

The alias template safe_iterator_t returns the iterator type of R, wrapped in dangling if the range was an rvalue range (as indicated by R not being an lvalue reference type).

They are used by range algorithms that accept rvalue ranges and return iterators into them.

Member functions

std::experimental::ranges::dangling::dangling

dangling( ) requires DefaultConstructible<T> ( ) ;
(1)
dangling(T t);
(2)
1) Default constructor. Value-initializes the wrapped object.
2) Initializes the wrapped object with t. Note that this constructor defines an implicit conversion from T to dangling<T>.

std::experimental::ranges::dangling::get_unsafe

T get_unsafe() const;

Returns a copy of the wrapped object.