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Check authorization with types

@RiccardoOdone•Suggest a tip•

Moving authorization from value to type level can make your code simpler and bullet-proof.

const dropDatabase = (performedBy: User) => {
  if (performedBy.type === 'MEBMER') { // ⛔️ Typo
    return
  }
  // ...
}

dropDatabase(member) // ⛔️

type User = Admin | Member

const dropDatabase = (performedBy: Admin) => {
  // ...
}

dropDatabase(member) // ✅ Does not compile
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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