Optional Chaning in Typescript

optionalChain.ts

/**
 * Optional Chaining in Typescript
 * lets you safely access nested properties, while preserving type information
 *
 * Usage:
 * type TData = { foo: Optional<{ bar: Optional<number> }> }
 * const data: TData = { foo: undefined }
 * const num = optionalChain(() => data.foo!.bar)
 */
type Optional<T> = T | undefined

export function optionalChain<T extends () => unknown>(getValue: T): Optional<ReturnType<T>>
export function optionalChain(getValue: () => unknown) {
  let value
  try {
    value = getValue()
  } catch (e) {}
  return value
}