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Rule proposal: Disallow optional chaining on undeclared variables
See original GitHub issueIt’s unfortunate that ?. is sugar for x !== undefined and not typeof x !== 'undefined'. The subtle difference is that the first one will fail if x is not defined at all.
Would it make sense to disallow the operator unless the variable is in the scope?
Fail
iDontExist?.meNeither
Pass
globalThis.iDontExist?.meNeither
let iDontExist;
iDontExist?.meNeither
Issue Analytics
- State:
- Created 2 years ago
- Reactions:1
- Comments:11 (7 by maintainers)
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Ah, it can also be optional call,
no-optional-chaining-on-undeclared-variableis better, if this rule also check optional call, and I think we should.no-undeclared-variable-optional-member?