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operator-(ranges::chunk_view::outer-iterator)

friend constexpr difference_type operator-( std::default_sentinel_t s,
                                            const /*outer-iterator*/& i )
    requires ranges::sized_sentinel_for<ranges::sentinel_t<V>,
                                        ranges::iterator_t<V>>;
 (1) (since C++23) 
friend constexpr difference_type operator-( const /*outer-iterator*/& i,
                                            std::default_sentinel_t s )
    requires ranges::sized_sentinel_for<ranges::sentinel_t<V>,
                                        ranges::iterator_t<V>>;
 (2) (since C++23)

Calculates the distance (in number of chunks) between the iterator and sentinel.

Let parent_ be the underlying pointer to enclosing chunk_view.

1) Equivalent to: 
const auto dist = ranges::end(i.parent_->base_) - *i.parent_->current_;
if (dist < i.parent_->remainder_)
    return dist == 0 ? 0 : 1;
return /*div-ceil*/(dist - i.parent_->remainder_, i.parent_->n_) + 1;
2) Equivalent to: return -(s - i);.

These functions are not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::ranges::chunk_view::outer-iterator is an associated class of the arguments.

Parameters

i - the iterator
s - the sentinel

Return value

The distance between given iterator and sentinel.

Example

See also

(C++23)
increments the iterator
(public member function)

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