std::counted_iterator<I>::count

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Iterator library

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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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constexprstd::iter_difference_t<I> count()constnoexcept;		(since C++20)

Returns the underlyinglength that is the distance to the end.

[edit]Parameters

(none)

[edit]Return value

The underlyinglength.

[edit]Example

Run this code

#include <cassert>#include <iostream>#include <iterator> int main(){constexprstaticauto il={1,2,3,4,5};constexprstd::counted_iterator i1{il.begin()+1,3};    static_assert(i1.count()==3);auto i2{i1};for(;std::default_sentinel!= i2;++i2)std::cout<<"*i2: "<<*i2<<", count(): "<< i2.count()<<'\n';assert(i2.count()==0);}

Output:

*i2: 2, count(): 3*i2: 3, count(): 2*i2: 4, count(): 1

[edit]See also

base	accesses the underlying iterator (public member function)[edit]

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std::counted_iterator<I>::count

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