1 ;;; idlw-complete-structtag.el --- Completion of structure tags.
3 ;; Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
4 ;; Free Software Foundation, Inc.
6 ;; Author: Carsten Dominik <dominik@astro.uva.nl>
7 ;; Maintainer: J.D. Smith <jdsmith@as.arizona.edu>
11 ;; This file is part of GNU Emacs.
13 ;; GNU Emacs is free software; you can redistribute it and/or modify
14 ;; it under the terms of the GNU General Public License as published by
15 ;; the Free Software Foundation; either version 3, or (at your option)
18 ;; GNU Emacs is distributed in the hope that it will be useful,
19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ;; GNU General Public License for more details.
23 ;; You should have received a copy of the GNU General Public License
24 ;; along with GNU Emacs; see the file COPYING. If not, write to the
25 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
26 ;; Boston, MA 02110-1301, USA.
30 ;; Completion of structure tags can be done automatically in the
31 ;; shell, since the list of tags can be determined dynamically through
32 ;; interaction with IDL.
34 ;; Completion of structure tags in a source buffer is highly ambiguous
35 ;; since you never know what kind of structure a variable will hold at
36 ;; runtime. To make this feature useful in source buffers, we need a
37 ;; special assumption/convention. We will assume that the structure is
38 ;; defined in the same buffer and directly assigned to the correct
39 ;; variable. This is mainly useful for applications in which there is one
40 ;; main structure which contains a large amount of information (and many
41 ;; tags). For example, many widget applications define a "state" structure
42 ;; that contains all important data about the application. The different
43 ;; routines called by the event handler then use this structure. If you
44 ;; use the same variable name for this structure throughout your
45 ;; application (a good idea for many reasons), IDLWAVE can support
46 ;; completion for its tags.
48 ;; This file is a completion plugin which implements this kind of
49 ;; completion. It is also an example which shows how completion plugins
50 ;; should be programmed.
52 ;; New versions of IDLWAVE, documentation, and more information available
58 ;; Put this file on the emacs load path and load it with the following
59 ;; line in your .emacs file:
61 ;; (add-hook 'idlwave-load-hook
62 ;; (lambda () (require 'idlw-complete-structtag)))
66 ;; Suppose your IDL program contains something like
70 ;; where the star marks the cursor position. If you now press the
71 ;; completion key M-TAB, IDLWAVE searches the current file for a
72 ;; structure definition
74 ;; state = {tag1:val1, tag2:val2, ...}
76 ;; and offers the tags for completion.
78 ;; In the idlwave shell, idlwave sends a "print,tag_names()" for the
79 ;; variable to idl and determines the current tag list dynamically.
83 ;; - The structure definition assignment "state = {...}" must use the
84 ;; same variable name as the the completion location "state.*".
85 ;; - The structure definition must be in the same file.
86 ;; - The structure definition is searched backwards and then forward
87 ;; from the current position, until a definition with tags is found.
88 ;; - The file is parsed again for each new completion variable and location.
89 ;; - You can force an update of the tag list with the usual command
90 ;; to update routine info in IDLWAVE: C-c C-i
94 (declare-function idlwave-shell-buffer
"idlw-shell")
96 ;; Some variables to identify the previously used structure
97 (defvar idlwave-current-tags-var nil
)
98 (defvar idlwave-current-tags-buffer nil
)
99 (defvar idlwave-current-tags-completion-pos nil
)
101 ;; The tag list used for completion will be stored in the following vars
102 (defvar idlwave-current-struct-tags nil
)
103 (defvar idlwave-sint-structtags nil
)
105 ;; Create the sintern type for structure talks
106 (declare-function idlwave-sintern-structtag
"idlw-complete-structtag" t t
)
107 (idlwave-new-sintern-type 'structtag
)
109 ;; Hook the plugin into idlwave
110 (add-to-list 'idlwave-complete-special
'idlwave-complete-structure-tag
)
111 (add-hook 'idlwave-update-rinfo-hook
'idlwave-structtag-reset
)
113 ;;; The main code follows below
114 (defvar idlwave-completion-help-info
)
115 (defun idlwave-complete-structure-tag ()
116 "Complete a structure tag.
117 This works by looking in the current file for a structure assignment to a
118 variable with the same name and takes the tags from there. Quite useful
119 for big structures like the state variables of a widget application.
121 In the idlwave shell, the current content of the variable is used to get
122 an up-to-date completion list."
126 (case-fold-search t
))
128 ;; Check if the context is right.
129 ;; In the shell, this could be extended to expressions like
130 ;; x[i+4].name.g*. But it is complicated because we would have
131 ;; to really parse this expression. For now, we allow only
132 ;; substructures, like "aaa.bbb.ccc.ddd"
133 (skip-chars-backward "[a-zA-Z0-9._$]")
134 (setq start
(point)) ;; remember the start of the completion pos.
136 (not (equal (char-before) ?
!)) ; no sysvars
137 (looking-at "\\([a-zA-Z][.a-zA-Z0-9_]*\\)\\.")
138 (>= pos
(match-end 0))
139 (not (string= (downcase (match-string 1)) "self"))))
140 (let* ((var (downcase (match-string 1))))
141 ;; Check if we need to update the "current" structure. Basically we
142 ;; do it always, except for subsequent completions at the same
143 ;; spot, to save a bit of time. Implementation: We require
145 ;; - the variable is different or
146 ;; - the buffer is different or
147 ;; - we are completing at a different position
148 (if (or (not (string= var
(or idlwave-current-tags-var
"@")))
149 (not (eq (current-buffer) idlwave-current-tags-buffer
))
150 (not (equal start idlwave-current-tags-completion-pos
)))
151 (idlwave-prepare-structure-tag-completion var
))
152 (setq idlwave-current-tags-completion-pos start
)
153 (setq idlwave-completion-help-info
154 (list 'idlwave-complete-structure-tag-help
))
155 (idlwave-complete-in-buffer 'structtag
'structtag
156 idlwave-current-struct-tags nil
157 "Select a structure tag" "structure tag")
158 t
) ; we did the completion: return t to skip other completions
159 nil
))) ; return nil to allow looking for other ways to complete
161 (defun idlwave-structtag-reset ()
162 "Force an update of the current structure tag list upon next use."
163 (setq idlwave-current-tags-buffer nil
))
165 (defvar idlwave-structtag-struct-location nil
166 "The location of the structure definition, for help display.")
168 (defun idlwave-prepare-structure-tag-completion (var)
169 "Find and parse the tag list for structure tag completion."
170 ;; This works differently in source buffers and in the shell
171 (if (eq major-mode
'idlwave-shell-mode
)
172 ;; OK, we are in the shell, do it dynamically
174 (message "preparing shell tags")
175 ;; The following call puts the tags into `idlwave-current-struct-tags'
176 (idlwave-complete-structure-tag-query-shell var
)
178 (setq idlwave-sint-structtags nil
179 idlwave-current-tags-buffer
(current-buffer)
180 idlwave-current-tags-var var
181 idlwave-structtag-struct-location
(point)
182 idlwave-current-struct-tags
184 (list (idlwave-sintern-structtag x
'set
)))
185 idlwave-current-struct-tags
))
186 (if (not idlwave-current-struct-tags
)
187 (error "Cannot complete structure tags of variable %s" var
)))
188 ;; Not the shell, so probably a source buffer.
192 (goto-char (point-max))
193 ;; Find possible definitions of the structure.
194 (while (idlwave-find-structure-definition var nil
'all
)
195 (let ((tags (idlwave-struct-tags)))
198 (setq idlwave-sint-structtags nil
199 idlwave-current-tags-buffer
(current-buffer)
200 idlwave-current-tags-var var
201 idlwave-structtag-struct-location
(point)
202 idlwave-current-struct-tags
204 (list (idlwave-sintern-structtag x
'set
)))
207 (error "Cannot complete structure tags of variable %s" var
))))
209 (defun idlwave-complete-structure-tag-query-shell (var)
210 "Ask the shell for the tags of the structure in variable or expression VAR."
211 (idlwave-shell-send-command
212 (format "if size(%s,/TYPE) eq 8 then print,tag_names(%s)" var var
)
213 'idlwave-complete-structure-tag-get-tags-from-help
216 (defvar idlwave-shell-prompt-pattern
)
217 (defvar idlwave-shell-command-output
)
218 (defun idlwave-complete-structure-tag-get-tags-from-help ()
219 "Filter structure tag name output, result to `idlwave-current-struct-tags'."
220 (setq idlwave-current-struct-tags
221 (if (string-match (concat "tag_names(.*) *\n"
222 "\\(\\(.*[\r\n]?\\)*\\)"
223 "\\(" idlwave-shell-prompt-pattern
"\\)")
224 idlwave-shell-command-output
)
225 (split-string (match-string 1 idlwave-shell-command-output
)))))
228 ;; Fake help in the source buffer for structure tags.
229 ;; kwd and name are global-variables here.
232 (defvar idlwave-help-do-struct-tag
)
233 (defun idlwave-complete-structure-tag-help (mode word
)
236 ;; fontify only in source buffers, not in the shell.
237 (not (equal idlwave-current-tags-buffer
238 (get-buffer (idlwave-shell-buffer)))))
241 idlwave-help-do-struct-tag idlwave-structtag-struct-location
))
242 (t (error "This should not happen"))))
244 (provide 'idlw-complete-structtag
)
246 ;;; idlw-complete-structtag.el ends here
249 ;; arch-tag: d1f9e55c-e504-4187-9c31-3c3651fa4bfa