Re: [PLUG] C #define wizardry question

[Jeff Weisberg <jaw+plug@tcp4me.com>]

| I'm trying to write a C macro like this:
| 
|     #define set(x) { x##_ = 1; printf("The variable "##x##"_ is set.\n");
|  }
| 
| So then I want to be able to say
| 
|     set(dog);
|     set(cat);
| 
| and have it expand to
| 
|     { dog_ = 1; printf("The variable dog_ is set.\n"); };
|     { cat_ = 1; printf("The variable cat_ is set.\n"); };
| 
| Unfortunately, the incantation in the printf doesn't work.


assuming ANSI C, you want #x which quotes x, yielding "dog"

#define set(x) { x##_ = 1; printf("The variable " #x "_ is set.\n"); }


	--jeff

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