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      std::basic_string_view<CharT,Traits>::front

      From cppreference.com
      <cpp‎ |string‎ |basic string view
       
       
       
      std::basic_string_view
       
      constexpr const_reference front()const;
      (since C++17)

      Returns reference to the first character in the view.

      Ifempty() istrue, the behavior is undefined.

      (until C++26)

      Ifempty() istrue:

      • If the implementation ishardened, acontract violation occurs. Moreover, if the contract-violation handler returns under “observe” evaluation semantic, the behavior is undefined.
      • If the implementation is not hardened, the behavior is undefined.
      (since C++26)

      Contents

      [edit]Return value

      data_[0]

      [edit]Complexity

      Constant.

      [edit]Example

      Run this code
      #include <iostream>#include <string_view> int main(){for(std::string_view str{"ABCDEF"};!str.empty(); str.remove_prefix(1))std::cout<< str.front()<<' '<< str<<'\n';}

      Output:

      A ABCDEFB BCDEFC CDEFD DEFE EFF F

      [edit]See also

      accesses the last character
      (public member function)[edit]
      checks whether the view is empty
      (public member function)[edit]
      (DR*)
      accesses the first character
      (public member function ofstd::basic_string<CharT,Traits,Allocator>)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/string/basic_string_view/front&oldid=182313"

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