Looking to create a new type based on the keys of another object in TypeScript.
Successfully achieved this through type inference. However, using an explicit type Record<string, something> results in keyof returning string instead of a union of the actual keys used.
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Check out this example code:
type FileType = "image" | "video" | "document";
type FileTypeList = Record<string, FileType>
const inferedFileList = {
a: "image",
b: "video",
c: "document"
}
//type files = "a" | "b" | "c"
type files = keyof typeof inferedFileList;
const explicitelyTypedList : FileTypeList = {
a: "image",
b: "video",
c: "document"
}
//type typedFiles = string
type typedFiles = keyof typeof explicitelyTypedList;
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Is it possible to use explicit typing like Record<string, something> and still obtain a union type with keyof? Perhaps there is a keyword that functions similarly to typeof, but utilizes the shape of an object instead of its declared type. Does TypeScript offer such functionality?