Mastering Type-Level Programming in TypeScript Cheat Sheet

Table of content

• Type Inference – Understanding how TypeScript determines types automatically
• Const Assertions – Making types as strict as possible
• Type Aliases & Interfaces – Creating reusable and flexible type definitions
• Function Overloads – Implementing multiple function signatures
• Declaration Merging – Combining multiple interfaces into one
• Readonly and Tuple Types – Working with immutable objects and fixed-length arrays
• Union & Intersection Types – Combining and narrowing types
• Generic Types & Conditions – Defining flexible types with constraints and defaults
• Type Guards & Type Assertions – Ensuring runtime type safety
• Structural Subtyping – Assigning types based on structure
• Mapped & Conditional Types – Transforming types dynamically
• Template String Literals – Creating string-based types