emacs.d/elpa/racket-mode-20200323.1739/racket-eldoc.el
2020-03-24 18:20:37 +01:00

47 lines
2 KiB
EmacsLisp

;;; racket-eldoc.el -*- lexical-binding: t -*-
;; Copyright (c) 2013-2020 by Greg Hendershott.
;; Portions Copyright (C) 1985-1986, 1999-2013 Free Software Foundation, Inc.
;; Author: Greg Hendershott
;; URL: https://github.com/greghendershott/racket-mode
;; License:
;; This is free software; you can redistribute it and/or modify it
;; under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version. This is distributed in the hope that it will be
;; useful, but without any warranty; without even the implied warranty
;; of merchantability or fitness for a particular purpose. See the GNU
;; General Public License for more details. See
;; http://www.gnu.org/licenses/ for details.
(require 'racket-cmd)
(defun racket--do-eldoc (how repl-session-id)
(and (racket--cmd-open-p)
(> (point) (point-min))
(save-excursion
(condition-case nil
;; The char-before and looking-at checks below are to
;; skip when the sexp is quoted or when its first elem
;; couldn't be a Racket function name.
(let* ((beg (progn
(backward-up-list)
(and (not (memq (char-before) '(?` ?' ?,)))
(progn (forward-char 1) (point)))))
(beg (and beg (looking-at "[^0-9#'`,\"]") beg))
(end (and beg (progn (forward-sexp) (point))))
(end (and end
(char-after (point))
(eq ?\s (char-syntax (char-after (point))))
end))
(sym (and beg end (buffer-substring-no-properties beg end)))
(str (and sym (racket--cmd/await repl-session-id
`(type ,how ,sym)))))
str)
(scan-error nil)))))
(provide 'racket-eldoc)
;; racket-eldoc.el ends here