operator-(std::basic_const_iterator)

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template < std::sized_sentinel_for <Iter> S >
constexpr difference_type operator- ( const S& s ) const ;
(1) (since C++23)
template < /*not-a-const-iterator*/ S >

requires std::sized_sentinel_for <S, Iter>
friend constexpr difference_type

    operator- ( const S& s, const basic_const_iterator& i ) ;
(2) (since C++23)

Returns the distance between basic_const_iterator and its sentinel.

S satisfies the exposition-only concept /*not-a-const-iterator*/ if and only if it's not a specialization of basic_const_iterator

Parameters

i, s - iterator and sentinel to compute the difference of

Return value

1) base() - s
2) s - i.base()

Example