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Modulesintermediate

Singleton Module

A singleton module ensures only one instance exists. ES modules are singletons by nature — re-importing the same module returns the cached instance. Simulate with a closure that tracks whether an instance was created.

💡 Hints (5)
  • • Use a closure to maintain instance and nextId state
  • • Check if instance already exists
  • • Only create a new instance if it does not exist
  • • Assign the id from nextId and increment nextId
  • • Return the same instance on subsequent calls