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All topics›JavaScript›Engine & memory

Attach data without leaking

advancedlayer A1 · Engine & memory5 tests

Write makeMetaStore() returning { set, get, has } that attaches data to objects.

  • two different objects never collide, even with identical contents
  • the store must not keep its keys alive — use a WeakMap

This is exactly how you tag DOM nodes without leaking them once they leave the page.

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