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09-type-programming/README.md

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+# Type Programming in TypeScript
+
+This example showcases advanced type-level programming in TypeScript using template literal types and recursive type definitions.
+
+We can define a type that parses a string literal at compile-time to extract placeholders and construct a corresponding object type.
+
+```typescript
+type ParseUrlParams<Url> = ...;
+
+function navigate<P extends string>(path: P, params: ParseUrlParams<P>) {
+  // ...
+}
+
+navigate("/book/{author}/{id}", { author: "foo", id: "bar" }); // Correct
+navigate("/book/{author}/{id}", { author: "foo" }); // -> 💥 Compiler Error: missing 'id'
+```
+
+This allows for extremely type-safe APIs, where the parameters required for a function are derived directly from a string template, ensuring that developers provide all necessary data.