std::ostream_iterator<T,CharT,Traits>:: ostream_iterator

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std::ostream_iterator
ostream_iterator ( ostream_type & stream, const CharT * delim ) ;
(1)
ostream_iterator ( ostream_type & stream ) ;
(2)

Constructs the iterator with stream as the associated stream, by storing the address of stream .

1) Uses delim as the delimiter.
2) Uses a null pointer as the delimiter.

Parameters

stream - the output stream to be accessed by this iterator
delim - the null-terminated character string to be inserted into the stream after each output

Example

Run this code 
#include <algorithm>
#include <iostream>
#include <iterator>
#include <numeric>
 
int main()
{
    std::ostream_iterator<char> oo{std::cout};
    std::ostream_iterator<int> i1{std::cout, ", "};
    std::fill_n(i1, 5, -1);
    *oo++ = '\n';
 
    std::ostream_iterator<double> i2{std::cout, "; "};
    *i2++ = 3.14;
    *i2++ = 2.71;
    *oo++ = '\n';
 
    std::common_iterator<std::counted_iterator<std::ostream_iterator<float>>,
                         std::default_sentinel_t>
        first{std::counted_iterator{std::ostream_iterator<float>{std::cout," ~ "}, 5}},
        last{std::default_sentinel};
    std::iota(first, last, 2.2);
    *oo++ = '\n';
}

Output: 

-1, -1, -1, -1, -1,
3.14; 2.71;
2.2 ~ 3.2 ~ 4.2 ~ 5.2 ~ 6.2 ~

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 1280 C++98 stream was stored directly stores its address instead
P2325R3 C++20 default constructor was provided as C++20
iterators must be default_initializable 		removed along with
the requirement
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