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fix(curriculum): correct WeakSet example with valid references#66981
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yoehae wants to merge 3 commits intofreeCodeCamp:mainfrom
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fix(curriculum): correct WeakSet example with valid references#66981yoehae wants to merge 3 commits intofreeCodeCamp:mainfrom
yoehae wants to merge 3 commits intofreeCodeCamp:mainfrom
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majestic-owl448
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Apr 20, 2026
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please update the output snippet below to be
WeakSet {{…}, {…}, {…}}
[[Entries]]
0: value: {name: 'Mopane Tree'}
1: value: {name: 'Baobab'}
2: value: {name: 'Breadfruit'}
[[Prototype]]: WeakSetand the paragraph "The contents appear empty because WeakSets are not iterable and do not expose their contents directly."
to
The contents are visible here because the object variables still hold strong references, keeping those objects in memory. Keep in mind that WeakSets are not iterable, so there is no way to loop over their entries or access them programmatically. What you see in the output is only a debugging aid.
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Checklist:
mainbranch of freeCodeCamp.Closes #66982
Update the
WeakSetexample to pass object variables totreeWeakSet.add()instead of object literals, and to pass an object variable totreeWeakSet.has()instead of a string..add()leaves no variable bound to the added object, so there is no way to reference it later. A subsequent.has()call with a literal that looks identical will still returnfalse, because each literal evaluates to a distinct object andWeakSetcompares entries by reference identity.WeakSetholds only weak references, an object added via a bare literal has no remaining strong reference once the statement completes, making it eligible for garbage collection and liable to disappear from the set before any later check..has()always returns false, becauseWeakSetcan only store objects. Strings are not valid entries.Note: resubmitting after a previous web-UI PR was deprioritized. Verified locally in a Codespace with
FCC_BLOCK='lecture-working-with-maps-and-sets'pnpm run develop, confirmed the corrected code renders on the lesson page.Opened a tracking issue at #66982 and linked it in the description. Will wait for triage before expecting review.