The time you enjoy wasting is not wasted time.
– Bertrand Russell
Not all standard-library components come as part of obviously labeled facilities, such as “containers” or “I/O.” This section gives a few examples of small, widely useful components. The point here is that a function or a type need not be complicated or closely tied to a mass of other functions and types to be useful. Such library components mostly act as building blocks for more powerful library facilities, including ...