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operator==,!=(std::istream_iterator<T, CharT, Traits, Dist>)

Defined in header <iterator> 
template< class T, class CharT, class Traits, class Dist >
bool operator==( const std::istream_iterator<T, CharT, Traits, Dist>& lhs,
                 const std::istream_iterator<T, CharT, Traits, Dist>& rhs );
 (1) 
template< class T, class CharT, class Traits, class Dist >
bool operator!=( const std::istream_iterator<T, CharT, Traits, Dist>& lhs,
                 const std::istream_iterator<T, CharT, Traits, Dist>& rhs );
 (2) (until C++20) 
friend bool operator==( const istream_iterator& i, std::default_sentinel_t );
 (3) (since C++20)

Checks whether both lhs and rhs are equal. Two stream iterators are equal if both of them are end-of-stream iterators or both of them refer to the same stream.

1) Checks whether lhs is equal to rhs.
2) Checks whether lhs is not equal to rhs.
3) Checks whether lhs is an end-of-stream iterator.
This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::istream_iterator<T, CharT, Traits, Dist> is an associated class of the arguments.

The != operator is synthesized from operator==.

 (since C++20)

Parameters

lhs, rhs - stream iterators to compare

Return value

1) true if lhs is equal to rhs, false otherwise.
2) true if lhs is not equal to rhs, false otherwise.
3) true if lhs is an end-of-stream iterator, false otherwise.

Exceptions

May throw implementation-defined exceptions.

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 261 C++98 the description of operator!= was missing added

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