object-keys.ts

/* eslint-disable @typescript-eslint/ban-types */

export type ObjectKeys<T extends object> = `${Exclude<keyof T, symbol>}`;

/**
A strongly-typed version of `Object.keys()`.

This is useful since `Object.keys()` always returns an array of strings. This function returns a strongly-typed array of the keys of the given object.

- [Explanation](https://stackoverflow.com/questions/55012174/why-doesnt-object-keys-return-a-keyof-type-in-typescript)
- [TypeScript issues about this](https://github.com/microsoft/TypeScript/issues/45390)

@example
```
import {objectKeys} from 'ts-extras';

const stronglyTypedItems = objectKeys({a: 1, b: 2, c: 3}); // => Array<'a' | 'b' | 'c'>
const untypedItems = Object.keys(items); // => Array<string>
```

@category Improved builtin
@category Type guard
*/
export const objectKeys = Object.keys as <Type extends object>(value: Type) => Array<ObjectKeys<Type>>;