return editor for all core command types

packages/core/src/commands/selectAll.ts

@@ -1,15 +1,15 @@
 import { Editor } from '../Editor'
 import { selectAll } from 'prosemirror-commands'
 
-type SelectAll = () => any
+type SelectAllCommand = () => Editor
 
 declare module '../Editor' {
   interface Editor {
-    selectAll: SelectAll,
+    selectAll: SelectAllCommand,
   }
 }
 
-export default (next: Function, { state, view }: Editor): SelectAll => () => {
+export default (next: Function, { state, view }: Editor) => () => {
   selectAll(state, view.dispatch)
   next()
 }