Incrementing enum values by a fixed number in C -


is possible increment values of fields of enum fixed number?

say if have enum

typedef enum {     val_a,     val_b,     val_c }enum_x;

i want define enum in such way values may increment fixed number (other 1 default). result in me having (let's number 4)

val_a = 4; val_b = 8; val_c = 12;

also if above answer true, , there such mechanism, possible make values increment sequentially?

say i've same enum redefined 

typedef enum {     #ifdef     val_a,     #endif      #ifdef b     val_b,     #endif      #ifdef c     val_c,     #endif      val_end }enum_x;

and if above enum define , c, should get

val_a = 4; val_c = 8;

but if define b , c, should get

val_b = 4; val_c = 8;

and if define a, b , c, should get

val_a = 4; val_b = 8; val_c = 12;

no, there's no such support in language.

you might able more or less horrible using macros of course. think whole "automatically" part troublesome, people can come troublesome preprocessor constructs when motivated enough.


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