```typescript
/** a divided by b. */
export function safeDivide(a: number, b: number): number {
  if (typeof a !== 'number' || typeof b !== 'number') {
    throw new Error('Both arguments must be numbers');
  }
  
  if (!isFinite(a) || !isFinite(b)) {
    throw new Error('Both arguments must be finite');
  }
  
  if (b === 0 || b === -0){
    throw new Error('Divisor cannot be zero');
  }
  
  return a / b;
}
```