std::istreambuf_iterator::istreambuf_iterator
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                    < cpp | iterator | istreambuf iterator
                    
                                                            
                    | (1) | ||
| istreambuf_iterator(); | (until C++11) | |
| constexpr istreambuf_iterator(); | (since C++11) | |
| istreambuf_iterator( std::basic_istream<CharT,Traits>& is ); | (2) | |
| istreambuf_iterator( std::basic_streambuf<CharT,Traits>* s ); | (3) | |
| istreambuf_iterator( const istreambuf_iterator& ) = default; | (4) | (since C++11) | 
1) Constructs an end-of-stream iterator.
2) Initializes the iterator and stores the value of is.rdbuf() in a data member. If is.rdbuf() is null, then end-of-stream iterator is constructed. 
3) Initializes the iterator and stores the value of 
s in a data member. If s is null, then end-of-stream iterator is constructed. 4) The copy constructor is explicitly defaulted.
[edit] Parameters
| is | - | stream to obtain the stream buffer from | 
| s | - | stream buffer to initialize the iterator with | 
[edit] Exceptions
1-4) 
noexcept specification:  
noexcept
  

