Menene alamomin fihirisa?

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**Alamar fihirisa** yana bayyana nau'i na malma'i lokacin da ba ka sani sunyansu kafin lokaci — yana buqata dictionaries/taswirori inda mabugi suke da kuzari. ```ts interface StringMap { [key: string]: number; // any string key maps to a number } const scores: StringMap = { math: 90, science: 85 }; scores.history = 70; // ✅ any string key allowed scores.math; // number scores.unknownKey; // number (TS assumes it exists!) — a caveat ``` ## Jita'adi na karewa Tare da alamar fihirisa mai tsauri, konpila yana ɗauka cewa **kowane** mabugi akwai, don haka `scores.typo` ana buqa shi azaman `number` ko da yake shi ne `undefined` a lokacin aiki. Kunna `noUncheckedIndexedAccess` yana gyara wannan: ```ts // with noUncheckedIndexedAccess: true scores.math; // number | undefined → forces you to handle the missing case ``` ## Haɗa madaidaita da mabugi masu nauyi ```ts interface Config { name: string; // known property [key: string]: string | number; // plus arbitrary extra keys } ``` Duk sanannun malma'i dole ne su kasance masu juriya ga nau'in ƙima na alamar fihirisa. ## Bayani yake kasancewa mafi kyau ```ts type Scores = Record; // same as the index signature type Roles = Record<"admin" | "user", boolean>; // constrained keys ``` `Record` shine gajeren kalamun idiom kuma yana goyan bayan ƙaƙƙarfan mabugi haddu, wanda maɗaɗɗe `[key: string]` ba zai iya yin ba. ## Me yasa ya mahalci Alamar fihirisa tana buqata abubuwan da ainihi masu mabugi na kuzari (tebur na neman, ajiyar, taswirori na JSON da aka karya). Sani jita'adi na karewa (`noUncheckedIndexedAccess`) kuma gwada `Record` don ƙarancewa — kuma gwada `Map` lokacin da mabugi suke da bubuwa da ba'a gida kuma kana so don gaske jerewa/girki semantics.