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Zero null

@RiccardoOdone•Suggest a tip•

Don't allow nulls if you can represent a "zero" with the base type.

type Balance = number | null
const balance = null // ⛔️ 0 would do it

type Transactions = number[] | null
const transactions = null // ⛔️ [] would do it

type Balance = number // ✅ null is invalid
type Transactions = number[] // ✅ null is invalid
Type-safe carouselDo not throwFilter using a type assertionUse precise typesType-safe string templatingEnumerating a union typeNumbers with unitsZero nullEnumerating statusesAnd typesAvoiding window as anyUse descriptive valuesCheck authorization with typesExtract union types from record typesKeep in sync with conditional typesType-safe pickPass arguments by namePick instead of duplicatingPrevent mutationsType aliasesModel with different typesPrefer static types over testsPush conditionals downType-level functionsCheck Authorization With Types (again)From Union to TupleLimit typesLaser-focused typesCallable typesPartial considered harmfulSatisfy typesWTH?!Parse, don't castNarrow typesFetch footgunModel with different types (2)Polymorphic typesParse, don't cast (again)Type-safe envObject vs Recordconst Type ParametersDigType checksExpand intellisenseNumbers with units (2)Unchecked indexed accessExtract instead of duplicating

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