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      std::chrono::month::operator++,std::chrono::month::operator--

      From cppreference.com
      <cpp‎ |chrono‎ |month
       
       
      Date and time library
       
       
      constexprstd::chrono::month& operator++()noexcept;
      (1)(since C++20)
      constexprstd::chrono::month operator++(int)noexcept;
      (2)(since C++20)
      constexprstd::chrono::month& operator--()noexcept;
      (3)(since C++20)
      constexprstd::chrono::month operator--(int)noexcept;
      (4)(since C++20)

      Adds or subtracts 1 from the month value, reducing the result modulo 12 to an integer in the range[112].

      1,2) Performs*this+=std::chrono::months{1};.
      3,4) Performs*this-=std::chrono::months{1};.

      Contents

      [edit]Parameters

      (none)

      [edit]Return value

      1,3) A reference to thismonth after modification.
      2,4) A copy of themonth made before modification.

      [edit]Notes

      After a call to one of these functions,ok() is alwaystrue.

      [edit]Example

      Run this code
      #include <cassert>#include <chrono>#include <iostream> int main(){std::chrono::month m{6}; ++m;assert(m==std::chrono::month(7)); --m;assert(m==std::chrono::month(6));     m=std::chrono::December;    m++;// rounds up to Januaryassert(m.ok());std::cout<<unsigned(m)<<'\n';     m=std::chrono::January;    m--;// rounds down to Decemberassert(m.ok());std::cout<<unsigned(m)<<'\n';}

      Output:

      112

      [edit]See also

      adds or subtracts a number of months
      (public member function)[edit]
      performs arithmetic onmonths
      (function)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/chrono/month/operator_inc_dec&oldid=157327"

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