Debugger entered--Lisp error: (invalid-function ("~/foo"))
  ("~/foo")("~/bin/")
  read-file-name-internal("~/bin/" "~/" lambda)
  minibuffer-complete()
* call-interactively(minibuffer-complete)
  read-file-name("Foo: " "~/" nil nil nil ("~/foo"))
  (condition-case err (read-file-name "Foo: " "~/" nil nil nil foo-history) (error (message "caught error: %s" err)))
  (let ((foo-history ...)) (condition-case err (read-file-name "Foo: " "~/" nil nil nil foo-history) (error ...)))
  foo()
* call-interactively(foo)
  execute-extended-command(nil)
* call-interactively(execute-extended-command)