std::span<T,Extent>::first
| template< std::size_t Count > constexpr std::span<element_type, Count> first() const; | ||
| constexpr std::span<element_type, std::dynamic_extent> first( std::size_t Count ) const; | 
Obtains a span that is a view over the first Count elements of this span. The behavior is undefined if Count > size().
Return value
A span r that is a view over the first Count elements of *this, such that r.data() == this->data() && r.size() == Count.
See also
| obtains a subspan consisting of the last N elements of the sequence (public member function) | |
| obtains a subspan (public member function) | 
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