casting - How to define a data type from file in C++? -

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i'm making class object should contain value, value read externally in form of value, datatype, datatype tells me how interpret given value (int, float, double, char, etc).

i wonder if possible make casting @ run time , how it, honest i'm bit lost , information i've found topic seems bit bit of overkill.

any ideas ? thanks.

look discriminated unions , boost::variant in particular, gist is:

struct value {   enum { int, float, double, char, etc } type;   union {     int int_;     float float_;     double double_;     char char_;     etc etc_;   } value; };

then check type before doing operation, , select right union member based on has been stored in it.


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