Unions on Dev & Platform Engineering Hub

TS Ep 42: Distributive Conditional Types

Sun, 09 Aug 2026 12:40:00 +0000

When you pass a Union type into a conditional type, TypeScript doesn’t evaluate the union as a whole. It evaluates every single member of the union separately, and combines the results. Learn how this powerful (and sometimes confusing) mechanism powers TypeScript’s standard library.

TS Ep 36: Built-in Utility Types (`Extract` and `Exclude`)

Sun, 09 Aug 2026 12:10:00 +0000

An in-depth guide to the Extract and Exclude utility types. Understand the fundamental difference between Object manipulation (Pick/Omit) and Union manipulation (Extract/Exclude), extracting by object signature in discriminated unions, and their underlying distributive conditional type mechanics.

TS Ep 7: Union and Intersection Types — Set Theory Mechanics

Sun, 09 Aug 2026 10:30:00 +0000

An in-depth analysis of Unions and Intersections in TypeScript. Understand how set theory models type relationships ($A \cup B$ vs $A \cap B$), property access rules, property conflict resolution to ’never’, and operator precedence.