about summary refs log tree commit diff
path: root/configs/shared/emacs/.emacs.d/elpa/haskell-mode-20180913.348/haskell-navigate-imports.el
blob: 7600d2305695abfcd56fc31d12c0a62eecc0deb1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
;;; haskell-navigate-imports.el --- A function for cycling through Haskell import lists -*- lexical-binding: t -*-

;; Copyright (C) 2010  Chris Done

;; Author: Chris Done <chrisdone@gmail.com>

;; This file is not part of GNU Emacs.

;; This program 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 3 of
;; the License, or (at your option) any later version.

;; This program 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.

;; You should have received a copy of the GNU General Public
;; License along with this program.  If not, see
;; <http://www.gnu.org/licenses/>.

;;; Commentary:

;; The cycling step will stop once at the last import list so
;; that it is easy to add a new import list.

;; This module works completely independently of any libraries
;; (including haskell-mode).

;; Exports three interactive functions:
;; 1. haskell-navigate-imports
;; 2. haskell-navigate-imports-go
;; 3. haskell-navigate-imports-return

;; Example usage:

;; (require 'haskell-navigate-imports)
;; (define-key haskell-mode-map (kbd "<f8>") 'haskell-navigate-imports)

;;; Code:

(defvar haskell-navigate-imports-start-point nil)

(defvar haskell-literate) ; defined in haskell-mode.el

;;;###autoload
(defun haskell-navigate-imports (&optional return)
  "Cycle the Haskell import lines or return to point (with prefix arg)."
  (interactive "P")
  (if return
      (haskell-navigate-imports-return)
    (haskell-navigate-imports-go)))

;;;###autoload
(defun haskell-navigate-imports-go ()
  "Go to the first line of a list of consecutive import lines. Cycles."
  (interactive)
  (unless (or (haskell-navigate-imports-line)
              (equal (line-beginning-position) (point-min))
              (save-excursion (forward-line -1)
                              (haskell-navigate-imports-line)))
    (setq haskell-navigate-imports-start-point (point)))
  (haskell-navigate-imports-go-internal))

;;;###autoload
(defun haskell-navigate-imports-return ()
  "Return to the non-import point we were at before going to the module list.
   If we were originally at an import list, we can just cycle through easily."
  (interactive)
  (when haskell-navigate-imports-start-point
    (goto-char haskell-navigate-imports-start-point)))

(defun haskell-navigate-imports-go-internal ()
  "Go to the first line of a list of consecutive import lines. Cycle."
  (if (haskell-navigate-imports-line)
      (progn (haskell-navigate-imports-goto-end)
             (when (haskell-navigate-imports-find-forward-line)
               (haskell-navigate-imports-go-internal)))
    (let ((point (haskell-navigate-imports-find-forward-line)))
      (if point
          (goto-char point)
        (progn (goto-char (point-min))
               (if (haskell-navigate-imports-find-forward-line)
                   (haskell-navigate-imports-go-internal)
                 (let ((module (if (eq haskell-literate 'bird)
                                   "^> ?module"
                                 "^module")))
                   (when (search-forward-regexp module nil t 1)
                     (search-forward "\n\n" nil t 1)))))))))

(defun haskell-navigate-imports-goto-end ()
  "Skip a bunch of consecutive import lines."
  (while (not (or (equal (point)
                         (point-max))
                  (not (haskell-navigate-imports-line))))
    (forward-line)))

(defun haskell-navigate-imports-find-forward-line ()
  "Return a point with at an import line, or nothing."
  (save-excursion
    (while (not (or (equal (point) (point-max))
                    (haskell-navigate-imports-after-imports-p) ;; This one just speeds it up.
                    (haskell-navigate-imports-line)))
      (forward-line))
    (if (haskell-navigate-imports-line)
        (point)
        nil)))

(defun haskell-navigate-imports-line ()
  "Try to match the current line as a regexp."
  (let ((line (buffer-substring-no-properties (line-beginning-position)
                                              (line-end-position)))
        (import (if (eq haskell-literate 'bird)
                    "^> ?import "
                  "^import ")))
    (if (string-match import line)
        line
      nil)))

(defun haskell-navigate-imports-after-imports-p ()
  "Are we after the imports list? Just for a speed boost."
  (save-excursion
    (goto-char (line-beginning-position))
    (not (not (search-forward-regexp "\\( = \\|\\<instance\\>\\| :: \\)"
                                     (line-end-position) t 1)))))

(provide 'haskell-navigate-imports)

;;; haskell-navigate-imports.el ends here