Type Narrowing

10 lessons

• 01Narrowing TypesLearn the process of making types more specific through code flow.
• 02Unknown TypeLearn why unknown is a safer alternative to the any type.
• 03Type HierarchyUnderstand the relationship between wide and narrow types.
• 04Narrowing Using InLearn how to use the in operator for structural type narrowing.
• 05Type PredicatesLearn how to create custom type guard functions.
• 06Exhaustive ChecksLearn how to ensure your code handles every member of a union.
• 07Guard ClausesLearn how to use early returns for cleaner type narrowing.
• 08Type AssertionLearn how to manually override TypeScript's type inference.
• 09Double AssertionLearn how to force an assertion between unrelated types.
• 10Non-Null AssertionLearn how to assert that a value is not null or undefined.