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Practice

Unions & Narrowing — Practice

intermediate~18 min of coding3 challenges

Runtime narrowing: typeof-based formatters, a discriminated-union reducer, and exhaustive switches with a default that throws.

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What you will practice

  1. Narrowing Formatterintermediate
  2. Discriminated Reducerintermediate
  3. Exhaustive Switchintermediate

Need the concept first? Re-read the lesson.