std::basic_spanstream<CharT,Traits>::span
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                    < cpp | io | basic spanstream
                    
                                                            
                    
| std::span<CharT> span() const noexcept; | (1) | (since C++23) | 
| void span( std::span<CharT> s ) noexcept; | (2) | (since C++23) | 
1) Gets a 
span referencing the written area if std::ios_base::out is set in the open mode of the wrapped std::basic_spanbuf, or a span referencing the underlying buffer otherwise.2) Makes the wrapped std::basic_spanbuf perform I/O on the buffer referenced by 
s.Parameters
| s | - | std::span referencing the storage to be use as the new underlying buffer of stream | 
Return value
1) A std::span referencing the underlying buffer or written area, depending on the open mode of the wrapped std::basic_spanbuf.
2) (none)
Example
| This section is incomplete Reason: no example | 
See also
| (C++23) | obtains or initializes an underlying buffer according to mode (public member function of std::basic_spanbuf<CharT,Traits>) |