Added types

src/index.ts

@@ -2,3 +2,4 @@ export * from './misc.js';
 export * from './numbers.js';
 export * from './objects.js';
 export * from './random.js';
+export * from './types.js';

src/objects.ts

@@ -1,11 +1,16 @@
-export const filterObject = (object: object, ...keys: string[]) => Object.fromEntries(Object.entries(object).filter(([key]) => keys.includes(key)));
+export function filterObject<T extends object, K extends keyof T>(object: T, ...keys: K[]): Omit<T, K> {
+	const entries = <[K, T[K]][]>Object.entries(object);
+	return <Omit<T, K>>(<unknown>Object.fromEntries(entries.filter(([key]) => keys.includes(key))));
+}
 
 import type * as FS from 'fs';
 
 let _fs: typeof FS;
 try {
 	_fs = await import('fs');
-} catch (e) {}
+} catch (e) {
+	_fs = null;
+}
 
 export function isJSON(str: string) {
 	try {

src/types.ts

@@ -0,0 +1,76 @@
+/**
+ * Expands the type T (for intellisense and debugging)
+ * @see https://stackoverflow.com/a/69288824/17637456
+ */
+export type Expand<T> = T extends (...args: infer A) => infer R ? (...args: Expand<A>) => Expand<R> : T extends infer O ? { [K in keyof O]: O[K] } : never;
+
+/**
+ * Recursivly expands the type T (for intellisense and debugging)
+ * @see https://stackoverflow.com/a/69288824/17637456
+ */
+export type ExpandRecursively<T> = T extends (...args: infer A) => infer R
+	? (...args: ExpandRecursively<A>) => ExpandRecursively<R>
+	: T extends object
+		? T extends infer O
+			? { [K in keyof O]: ExpandRecursively<O[K]> }
+			: never
+		: T;
+
+/**
+ * Extracts an object with properties assignable to P from an object T
+ * @see https://stackoverflow.com/a/71532723/17637456
+ */
+export type ExtractProperties<T, P> = {
+	[K in keyof T as T[K] extends infer Prop ? (Prop extends P ? K : never) : never]: T[K];
+};
+
+/**
+ * Extract the keys of T which are required
+ * @see https://stackoverflow.com/a/55247867/17637456
+ */
+// eslint-disable-next-line @typescript-eslint/ban-types
+export type RequiredKeys<T> = { [K in keyof T]-?: {} extends { [P in K]: T[K] } ? never : K }[keyof T];
+
+/**
+ * @see https://dev.to/tmhao2005/ts-useful-advanced-types-3k5e
+ */
+export type RequiredProperties<T extends object, K extends keyof T = keyof T> = Omit<T, K> & Required<Pick<T, K>>;
+
+/**
+ * @see https://dev.to/tmhao2005/ts-useful-advanced-types-3k5e
+ */
+export type DeepRequired<T> = {
+	[K in keyof T]: Required<DeepRequired<T[K]>>;
+};
+
+/**
+ * @see https://dev.to/tmhao2005/ts-useful-advanced-types-3k5e
+ */
+export type Optional<T, K extends keyof T> = Omit<T, K> & Partial<T>;
+
+/**
+ * @see https://dev.to/tmhao2005/ts-useful-advanced-types-3k5e
+ */
+export type NestedKeys<T extends object> = {
+	[P in keyof T & (string | number)]: T[P] extends Date ? `${P}` : T[P] extends Record<string, unknown> ? `${P}` | `${P}.${NestedKeys<T[P]>}` : `${P}`;
+}[keyof T & (string | number)];
+
+/**
+ * @see https://dev.to/tmhao2005/ts-useful-advanced-types-3k5e
+ */
+export type PartialRecursive<T> = {
+	[P in keyof T]?: T[P] extends (infer U)[] ? PartialRecursive<U>[] : T[P] extends object | undefined ? PartialRecursive<T[P]> : T[P];
+};
+
+/**
+ * Get the keys of a union of objects
+ * @see https://stackoverflow.com/a/65805753/17637456
+ */
+export type UnionKeys<T> = T extends T ? keyof T : never;
+
+type StrictUnionHelper<T, TAll> = T extends unknown ? T & Partial<Record<Exclude<UnionKeys<TAll>, keyof T>, never>> : never;
+
+/**
+ * @see https://stackoverflow.com/a/65805753/17637456
+ */
+export type StrictUnion<T> = Expand<StrictUnionHelper<T, T>>;