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  1. #include <iostream>
  2. #include <exception>
  3.  
  4. enum class Launches : std::uint32_t
  5. {
  6.   First = 0,
  7.  
  8.   D_FROM_FILE = First,
  9.   D_FROM_FDISK,
  10.   D_FROM_RDDISK,
  11.   D_FROM_USB,
  12.   D_FROM_UI,
  13.   D_FROM_NET,
  14.   D_FROM_DEFAULT,
  15.  
  16.   Last = D_FROM_DEFAULT
  17. };
  18.  
  19. template< typename E, typename T >
  20. Launches seq_enum_cast(T  v)
  21. {
  22.   return v >= static_cast<T>(E::First) && v <= static_cast<T>(E::Last)
  23.     ? static_cast<E>(v)
  24.     : throw std::bad_cast();
  25. }
  26.  
  27. int main()
  28. {
  29.   try
  30.   {
  31.     auto a = seq_enum_cast<Launches>(1);
  32.     std::cout << "a - success\n";
  33.     auto b = seq_enum_cast<Launches>(-3); // fails
  34.     std::cout << "b - success\n";
  35.   }
  36.   catch (const std::bad_cast& e)
  37.   {
  38.     std::cout << e.what();
  39.   }
  40. }
Success #stdin #stdout 0.01s 5460KB
comments (?)
stdin 
Standard input is empty
stdout 
a - success
std::bad_cast
https://ideone.com/zyG0x5
language:
C++14 (gcc 8.3)
created:
3 years ago
visibility:
public

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