Main.c

#include <stdio.h>

#define SHARP_OP_TEST(expr) (printf("#expr = %s, expr = %d\n", #expr, (expr)) )
#define var(i) printf("var" #i " = %d\n" , var ## i)
#define CONBINE(a, b) (printf("%s\n", a##b))

int main(void){
    const char test[] = "This is test";
    int var1 = 10;
    SHARP_OP_TEST(1+2);
    var(1);
    CONBINE(te,st);
    return 0;
}

// outputs
// #expr = 1+2, expr = 3
// var1 = 10
// This is test