Template literal types zinakuruhusu kujenga aina mpya za string literal kwa kuingiza aina zingine ndani ya template — manipulasi ya string kwenye kiwango cha type.
ts
= ;
: = ;
: = ;
type Color = "red" | "blue";
type Shade = "light" | "dark";
type Variant = `${Shade}-${Color}`;
// "light-red" | "light-blue" | "dark-red" | "dark-blue" — all combinations
Kompela inakuza kila mchanganyiko wa unions — muhimu kwa ajili ya kuzalisha seti halali za ufunguo wa string (CSS classes, event names, route patterns) kwa otomatiki.
type Entity = "user" | "post";
type Event = `${Entity}:${"created" | "deleted"}`;
// "user:created" | "user:deleted" | "post:created" | "post:deleted"
function on(event: Event, cb: () => void) {}
on("user:created", () => {}); // ✅
on("user:updated", () => {}); // ❌ not a valid event
type Getters<T> = {
[K in keyof T & string as `get${Capitalize<K>}`]: () => T[K];
};
// { name: string } → { getName: () => string }
Uppercase, Lowercase, Capitalize, Uncapitalize ni helper zilizojenga ndani.
Template literal types hufanya API zilizotegemeza string ziwe salama: route params, event systems, CSS-in-JS, jina la safuweka za ORM.
Badala ya kukubali string yoyote, unaweza kuzuia kwa seti sahihi, iliyozalishwa ya string halali — kukamata typos wakati wa kompilasyon mahali ambayo hapo awali yalikuwa string-based.