Add Re-Export An Imported Type as a TypeScript til

typescript/re-export-an-imported-type.md

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+# Re-Export An Imported Type
+
+I have a TypeScript module that is defining an XState machine. Among other
+things, it imports the `DoneEventObject` type from `xstate`. I want to
+re-export that type so that any modules using this machine have access to that
+type definition.
+
+This can be done a couple of ways. One way to import it under an aliased name
+and then assign + export it using the original name.
+
+```typescript
+import {Machine, DoneEventObject as _DoneEventObject} from 'xstate'
+
+export type DoneEventObject = _DoneEventObject
+```
+
+This works, but adds some potential indirection and confusion through the
+double assignment.
+
+Another way of doing this is to reference the type off the import statement as
+part of an assignment.
+
+```typescript
+import {Machine} from 'xstate'
+
+export type DoneEventObject = import('xstate').DoneEventObject
+```
+
+This imports, assigns, and exports the type in a single statement.
+
+[source](https://github.com/microsoft/TypeScript/issues/28481#issuecomment-552938424)