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

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std::istream_iterator
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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