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require explicit check for undefined?
See original GitHub issueThis code has a runtime error. It will not use the 0 value.
Should Hegel force us to explicitly check undefined to avoid the runtime error?
Issue Analytics
- State:
- Created 3 years ago
- Reactions:1
- Comments:11 (4 by maintainers)
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I think it would make sense to warn on
Nullish | PossblyFalsyused inif,while, ternary, etc. (whereNullishis either null or undefined or union of both, andPossiblyFalsyis any combination ofstring,number,bigintandboolean)This is what Flow does (with
sketchy-nulllint enabled), and there’sstrict-boolean-expressionsfor typescript-eslint which also does that.I don’t think a linter could do a good job checking these things, otherwise the linter would become something like Hegel already is.