Static, define, and const in C

Question

I\'ve read that static variables are used inside function when one doesn\'t want the variable value to change/initialize each time the function is called. But what about def

Answer 1

The main difference is that with #define you leave the type system. The preprocessor has no notion of type safety, scope etc. So e.g. if you later try to write a loop like

for (int m = 0; m < size; m++) { ... }

you are up to a nasty surprise...

Also if you use #defines, you will only see the value of 30000 when debugging your code, not the name m. Which does not seem to make a big difference in this case, but when using meaningful constant and variable names, it does indeed.