Repro

{
  "rules": {
    "typescript/no-use-before-define": ["error",{"typedefs": true}]
  }
}

// Should error according to docs, but it wont

let myVar: StringOrNumber = 'hello'
type StringOrNumber = string | number

Expected Result

Should work according to docs

Actual Result

Doesn't work at all

Additional Info

Also dunno if this is considered within the implementation, but there is a common pattern in React to get Props/State types from implementation by leveraging typeof. So if typedefs is set to false this should not raise any error:

type State = typeof initialState
const initialState = { count: 0, who: ''}

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