c preprocessor - Simple tuple operation -


say have tuple:

#define t (a, b)

how can extract first , second element of tuple in gcc, without use of external libraries?

i found 1 way of doing this. i'm not sure if work in else gcc.

#define first_(x, y) x #define first(t) first_ t  #define second_(x, y) y #define second(t) second_ t  #define t (a, b)  first(t) // expands second(t) // expands b

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