std::ranges::filter_view<V,Pred>::sentinel
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                    < cpp | ranges | filter view
                    
                                                            
                    | class /*sentinel*/; | (since C++20) (exposition only*) | |
The return type of filter_view::end when the underlying view type (V) does not model common_range.
Data members
Typical implementations of sentinel hold only one non-static data member: the sentinel of the underlying view (shown here as end_ for exposition only).
Member functions
| (C++20) | constructs a sentinel (public member function) | 
| (C++20) | returns the underlying sentinel (public member function) | 
std::ranges::filter_view::sentinel::sentinel
| /*sentinel*/() = default; | (1) | (since C++20) | 
| constexpr explicit /*sentinel*/( filter_view& parent ); | (2) | (since C++20) | 
std::ranges::filter_view::sentinel::base
| constexpr ranges::sentinel_t<V> base() const; | (since C++20) | |
Equivalent to return end_;.
Non-member functions
| (C++20) | compares the underlying iterator and the underlying sentinel (function) | 
operator==(std::ranges::filter_view::iterator, std::ranges::filter_view::sentinel)
| friend constexpr bool operator==( const /*iterator*/& x, const /*sentinel*/& y ); | (since C++20) | |
Equivalent to return x.current_ == y.end_;, where current_ is the underlying iterator wrapped in filter_view::iterator.
The != operator is synthesized from  operator==.
This function  is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::ranges::filter_view::sentinel is an associated class of the arguments.