# A gentle introduction to C* VIII

### Let us dig deep into the transient variable lifetimes that power law enforcement in C*.

Welcome to *part seven* of **A gentle introduction to C***. Today’s instalment is a special one, where we will finally dig into the *details* of how law enforcement is actually carried out in C*.

Let us have a program in C*:

```
typedef uint32_t myint;
/* Must be less than 100 and cannot ever equal 17 */
law : myint
{
_ < 100;
_ != 17;
};
/* Fibonacci sequence will satisfy both of those constraints, but how
* do we know? */
void fibonacci( void )
{
uint32_t i, n;
myint t0, t1;
uint32_t tn;
t0 = 0;
t1 = 1;
/* print the first two terms */
fprintf(stdout, "Fibonacci series: %d, %d", t0, t1);
/* print 3rd to 12th terms */
for(i = 2; i < 12; ++i)
{
tn = t0 + t1;
fprintf(stdout, ", %d", tn);
t0 = t1;
t1 = tn;
}
}
```

Going through the Fibonacci sequence, we know that if we limit the number of terms to 12, we will never reach 100. But how does the C* compiler break this down?

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