[Typescript] Utility Types

// Make all properties in T optional
type Partial<T> = {
	[P in keyof T]?: T[P]; 
}

// Make all properties in T required
type Required<T> = {
	[P in keyof T]: T[P];
}

// Make all properties in T readonly
type Readonly<T> = {
  	readonly [P in keyof T]: T[P];
}

// From T, pick a set of properties whose keys are in the union K
type Pick<T, K extends keyof T> = { [P in K]: T[P]; }

// Construct a type with a set of properties K of type T
type Record<K extends keyof any, T> = {
  	[P in K]: T;
}

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