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All topics›JavaScript›Scope & functions, properly

A counter nobody can cheat

beginnerlayer I1 · Scope & functions, properly5 tests

Write makeCounter() returning { inc, dec, get }.

  • inc() and dec() move the count and return the new value
  • get() reads it
  • the count itself must be unreachable from outside — no counter.count
  • two counters must not share anything

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