operator==(std::counted_iterator<I>, std::default_sentinel_t)

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Iterator library

Iterator concepts

indirectly_readable (C++20)
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weakly_incrementable (C++20)
incrementable (C++20)
is-integer-like is-signed-integer-like (C++20)(C++20)

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input_iterator (C++20)
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input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag

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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)
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(C++20)

(C++20)

(C++26)

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
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inserter
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common_iterator (C++20)
counted_iterator (C++20)
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const_sentinel (C++23)
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empty (C++17)
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std::counted_iterator

Member functions
counted_iterator::counted_iterator
counted_iterator::operator=
counted_iterator::base
counted_iterator::count
counted_iterator::operator*counted_iterator::operator->
counted_iterator::operator[]
counted_iterator::operator++counted_iterator::operator++(int)counted_iterator::operator+counted_iterator::operator+=counted_iterator::operator--counted_iterator::operator--(int)counted_iterator::operator-counted_iterator::operator-=
Non-member functions
operator==operator<=> (C++20)(C++20)
operator==(default_sentinel_t) (C++20)
operator+ (C++20)
operator- (C++20)
operator-(default_sentinel_t) (C++20)
iter_move (C++20)
iter_swap (C++20)
Helper classes
iterator_traits<std::counted_iterator> (C++20)

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friendconstexprbool operator==( const counted_iterator& x,std::default_sentinel_t);		(since C++20)

Checks if the underlyinglength (i.e. distance to the end) is equal to0.

This function template is not visible to ordinaryunqualified orqualified lookup, and can only be found byargument-dependent lookup when std::counted_iterator<I> is an associated class of the arguments.

The!= operator issynthesized fromoperator==.

[edit]Parameters

an iterator adaptor

[edit]Return value

true ifx.count() is equal to0,false otherwise.

[edit]Example

Run this code

#include <initializer_list>#include <iterator> int main(){staticconstexprauto v={1,2,3,4};constexprstd::counted_iterator<std::initializer_list<int>::iterator>        it1{v.begin(),3},        it2{v.begin(),0};    static_assert(it1!=std::default_sentinel);    static_assert(it2==std::default_sentinel);    static_assert(std::default_sentinel!= it1);    static_assert(std::default_sentinel== it2);}