istream_iterator( istream_type& stream );
istream_iterator( const istream_iterator& other ) = default;
1) Constructs the end-of-stream iterator, value-initializes the stored value. This constructor is constexpr if the initializer in the definition auto x = T(); is a constant initializer.
2) Initializes the iterator, stores the address of
streamin a data member, and performs the first read from the input stream to initialize the cached value data member.
3) Constructs a copy of
other. If std::is_trivially_copy_constructible_v<T> is
true, this copy constructor is a trivial copy constructor.
|stream||-||stream to initialize the istream_iterator with|
|other||-||another istream_iterator of the same type|
 Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
|DR||Applied to||Behavior as published||Correct behavior|
|P0738R2||C++98||the first read may be deferred to the first dereferencing||the first read is performed in the constructor|