Closure-Based Guards

HardClosures & ScopePRO

Model a rate-limit token bucket with JavaScript closure state, capacity rules, refill behavior, and independent bucket instances. This hard exercise focuses on guarding mutable private counters while exposing only take, refill, and remaining methods.

What you'll practice

Model a rate-limit token bucket with JavaScript closure state
Capacity rules
Refill behavior
Independent bucket instances
Guarding mutable private counters while exposing only take
Refill
Remaining methods

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