Debugger entered--Lisp error: (invalid-read-syntax "#")
  read-from-string("(#elisp--witness--lisp)")
  elisp--local-variables()
  #[257 …]("xx")
  #[771 …]("xx" nil nil)
  try-completion("xx" #[771 …] nil)
  #[257 …](#[771 …])
  mapcar(#[257 …] (#[771 …] (closure (t) (&rest args) (apply (quote completion-table-with-predicate) …))))
  #[771 …]("xx" nil nil)
  try-completion("xx" #[771 …] nil)
  completion-basic-try-completion("xx" #[771 …] nil 2)
  #[257 …](basic)
  completion--some(#[257 …] (basic partial-completion emacs22))
  completion--nth-completion(1 "xx" #[771 …] nil 2 (metadata))
  completion-try-completion("xx" #[771 …] nil 2 (metadata))
  completion--do-completion(#<marker at 7 in  *Minibuf-1*> 9)
  completion--in-region-1(#<marker at 7 in  *Minibuf-1*> 9)
  #[1028 …](#<marker at 7 in  *Minibuf-1*> … nil)
  apply(#[1028 …] (#<marker at 7 in  *Minibuf-1*> … nil))
  #[771 …](nil nil (#<marker at 7 in  *Minibuf-1*> … nil))
  completion--in-region(#<marker at 7 in  *Minibuf-1*> 9 #[771 …] nil)
  completion-in-region(#<marker at 7 in  *Minibuf-1*> 9 #[771 …] nil)
  completion-at-point()
  funcall-interactively(completion-at-point)
  call-interactively(completion-at-point nil nil)
  command-execute(completion-at-point)
  read-from-minibuffer("Eval: " nil (keymap …) t read-expression-history)
  read--expression("Eval: ")
  byte-code(… [current-prefix-arg read--expression "Eval: "] 2)
  call-interactively(eval-expression nil nil)
  command-execute(eval-expression)