std::istream_iterator::istream_iterator
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                    < cpp | iterator | istream iterator
                    
                                                            
                    | constexpr istream_iterator(); | (1) | |
| istream_iterator( istream_type& stream ); | (2) | |
| istream_iterator( const istream_iterator& other ) = default; | (3) | |
1) Constructs the end-of-stream iterator. This constructor is constexpr if std::is_trivially_default_constructible_v<T> is 
true .2) Initializes the iterator and stores the address of 
stream in a data member. Optionally, performs the first read from the input stream to initialize the cached value data member (although it may be delayed until the first access)3) Constructs a copy of 
other. If std::is_trivially_copy_constructible_v<T> is true , this copy constructor is a trivial copy constructor.[edit] Parameters
| stream | - | stream to initialize the istream_iterator with | 
| other | - | another istream_iterator of the same type | 
[edit] Examples
Run this code
#include <iostream> #include <iterator> #include <algorithm> #include <sstream> int main() { std::istringstream stream("1 2 3 4 5"); std::copy( std::istream_iterator<int>(stream), std::istream_iterator<int>(), std::ostream_iterator<int>(std::cout, " ") ); }
Output:
1 2 3 4 5


