[el-search] How to search string excluding docstring?

[Chunyang Xu]

Hi Michael Heerdegen and other Emacs users,

For example, with the following contents in a buffer

(defun foo ()
  "foo docstring"
  (message "foo string"))

(string "foo") matches both "foo docstring" and "foo string", I want a
way to exclude the docstring, by "docstring", I just mean the string
being checking should not be the fourth element in

  (defun _ _ docstring . _)

I am thinking a pattern like

  (and (pred stringp) (guard (not (docstring-p))) (string "foo"))

but I have no idea how to define 'docstring-p'.

Any tips?