Using a character name as a string literal in a #define function macro

I want the debug function macro to work like this:

int myVar = 5;
PRINTVAR(myVar); // macro

// which expands to something like...
print("myVar: ");


Basically, I want to use the identifier as a string literal as well as a variable.

I'm just a little tired of repeating myself when I want to dump a lot of variables to stdout.

My silly attempt, which of course doesn't work:

#define PRINT_VAR(x) Serial.print("x: "); Serial.println(x);


Is it possible?


source to share

3 answers

The "gating operator" is intended for this very case:

#define PRINT_VAR(x) (print(#x ": "), println(x))




Look at the contraction operator , #, when you use a macro prefix with this, it puts it as a string, not expands it.



Providing sample code, I don't know if you are talking about C or Java. However, here's what I'll do in C:

#define DEBUG(X, ...) fprintf(x, __VA_ARGS__);


And use it:

DEBUG (srderr, "my mistake \ n");



All Articles