/prelude/evil_casts.hpp

http://github.com/Eelis/geordi · C++ Header · 16 lines · 10 code · 4 blank · 2 comment · 0 complexity · 9a383cad833cf3ea04d7247d154ae475 MD5 · raw file 

    

  1. #ifndef EVIL_CASTS_HPP
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  2. #define EVIL_CASTS_HPP
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  4. // Consider   some_evil_cast<char const *>("foo")   . There are two possible interpretations for the result: either the array should decay into a pointer and be immediately returned, or the bytes making up the array are interpreted as the bytes making up the to-be-returned pointer. cast_dammit_cast does the former, while savage_cast does the latter.
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  6. template <typename To, typename From> To savage_cast (From const & from)
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  7. { return (To const &) from; }
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  8.   // Can even be used to check endianness:  geordi << hex << savage_cast<uint32_t>("\xef\xbe\xad\xde"))
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  10. template <typename To, typename From> To cast_dammit_cast (From const from)
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  11. {
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  12.   From const & r = from; // from itself is not a reference because we want arrays to decay, so that cast_dammit_cast<char*>("oi") works properly.
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  13.   return (To const &) r;
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  14. }
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  16. #endif // header guard
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