Type Definition

 

#include <stdio.h>

//.................................
//      <-new--> <----old------->
#define NEW_TEXT "OLD OLD OLD TEXT"
#define SUM       (i1 + i2)
//.................................


int main(void) {

 unsigned long int i1; // too many letters to type

 //...................................
 //      <--old type-----> <new type> ;
 typedef unsigned long int   MyULInt  ;
 //...................................

 MyULInt i2; // short, simple, good-looking

 i1 = 123UL;   // Unsigned Long integer constant, explicit
 i2 = 456UL;

 printf("%s \n", NEW_TEXT);

 printf("i1=%ld \n", i1);
 printf("i2=%ld \n", i2);
 printf("SUM=%ld \n", SUM);

}





OLD OLD OLD TEXT 
i1=123 
i2=456 
SUM=579