@univerjs/core v0.4.2 • Docs

Type Alias: Doc

type Doc: 
  | null
  | boolean
  | number
  | string
  | Doc[]
| {};

JSON documents must be able to round-trip through JSON.stringify / JSON.parse. So this means they can't contain:

• undefined
• Circular references
• Objects of classes
• Functions
• Sets, Maps, Dates, DOM nodes, etc

Defined in

submodules/univer/node_modules/.pnpm/ot-json1@1.0.2/node_modules/ot-json1/dist/types.d.ts:63