NewTokenBucketPassiveRateLimiter is similar to NewTokenBucketRateLimiter except that it returns a PassiveRateLimiter which does not have Accept() and Wait() methods.

NewTokenBucketPassiveRateLimiterWithClock is similar to NewTokenBucketRateLimiterWithClock except that it returns a PassiveRateLimiter which does not have Accept() and Wait() methods and uses a PassiveClock.

NewTokenBucketRateLimiter creates a rate limiter which implements a token bucket approach.

NewTokenBucketRateLimiterWithClock is identical to NewTokenBucketRateLimiter but allows an injectable clock, for testing.

An injectable, mockable clock interface.