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

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

Iterator library

Iterator concepts
indirectly_readable (C++20) indirectly_writable (C++20) weakly_incrementable (C++20) incrementable (C++20) is-integer-like is-signed-integer-like (C++20)(C++20)	sentinel_for (C++20) sized_sentinel_for (C++20) input_iterator (C++20) output_iterator (C++20) input_or_output_iterator (C++20)	forward_iterator (C++20) bidirectional_iterator (C++20) random_access_iterator (C++20) contiguous_iterator (C++20)
Iterator primitives
input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag (C++20)	iter_value_titer_difference_titer_reference_titer_const_reference_titer_rvalue_reference_titer_common_reference_t (C++20)(C++20)(C++20)(C++23)(C++20)(C++20)	iterator (deprecated in C++17) iterator_traits incrementable_traits (C++20) indirectly_readable_traits (C++20)
Algorithm concepts and utilities
Indirect callable concepts
indirectly_unary_invocableindirectly_regular_unary_invocable (C++20)(C++20)	indirect_unary_predicate (C++20) indirect_binary_predicate (C++20)	indirect_equivalence_relation (C++20) indirect_strict_weak_order (C++20)
Common algorithm requirements
indirectly_movable (C++20) indirectly_movable_storable (C++20) indirectly_copyable (C++20)	indirectly_copyable_storable (C++20)   indirectly_swappable (C++20) indirectly_comparable (C++20)	permutable (C++20) mergeable (C++20) sortable (C++20)
Utilities
indirect_result_t (C++20)	projected (C++20)	projected_value_t (C++26)
Iterator adaptors
reverse_iterator make_reverse_iterator (C++14) move_iterator (C++11) make_move_iterator (C++11) default_sentinel_tdefault_sentinel (C++20)(C++20) unreachable_sentinel_tunreachable_sentinel (C++20)(C++20)	front_insert_iterator back_insert_iterator inserter insert_iterator front_inserter back_inserter move_sentinel (C++20)	common_iterator (C++20) counted_iterator (C++20) basic_const_iterator (C++23) const_iterator (C++23) const_sentinel (C++23) make_const_iterator (C++23) make_const_sentinel (C++23)
Stream iterators istream_iterator    ostream_iterator istreambuf_iterator ostreambuf_iterator	Iterator customization points ranges::iter_move (C++20) ranges::iter_swap (C++20)
Iterator operations advance distance prev (C++11)   next (C++11) ranges::advance (C++20) ranges::distance (C++20) ranges::prev (C++20) ranges::next (C++20)	Range access begincbegin (C++11)(C++14) rbegincrbegin (C++14)(C++14)   endcend (C++11)(C++14) rendcrend (C++14)(C++14)   sizessize (C++17)(C++20) empty (C++17) data (C++17)

 

std::istream_iterator

Member functions

istream_iterator::istream_iterator

istream_iterator::~istream_iterator

istream_iterator::operator*istream_iterator::operator->

istream_iterator::operator++istream_iterator::operator++(int)

Non-member functions

operator==operator!= (until C++20)

 

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