```ts
/**
 * Safely divides `a` by `b`.
 *
 * @param {number} a - The dividend.
 * @param {number} b - The divisor.
 * @returns {number} - The result of the division.
 */
export function safeDivide(a: number, b: number): number {
  if (typeof a !== 'number' || typeof b !== 'number') {
    throw new Error('Both arguments must be numbers.');
  }
  if (b === 0 || b === -0) {
    throw new Error('Divisor cannot be zero.');
  }
  return a / b;
}
```