import { Doc } from "./types"

export default function deepClone(old: Doc): Doc {
  if (old === null) return null

  if (Array.isArray(old)) {
    return old.map(deepClone)
  } else if (typeof old === 'object') {
    const o: Doc = {}
    for (let k in old) o[k] = deepClone(old[k])
    return o
  } else {
    // Everything else in JS is immutable.
    return old
  }
}