gmj-ifdef.org 7.3 KB
CAVEAT
This is probably obsolete for two reasons:
-
hide-ifdef-mode exists https://www.emacswiki.org/emacs/HideIfDef
-
Using real cpp(1) directly probably makes more sense than re-implementing it in elisp. e.g. something like
cat resume-master.txt | cpp resume.tex | latex
Not precice, but that's the idea. Need to figure out how org fits in into all this (export resume-master.org ot resume-master.txt before the start of this pipeline?)
What
Code to do cpp ifdef-like substitution on org-mode export.
Why
Because I wanted to ifdef my resume for different versoins (LinkedIn, etc)
How
Define functions to implmenet #define, #ifdef, etc. Add as an org-mode export hook. Define keybindings.
See sample text below.
Who
George Jones <gmj@pobox.com>
When
To run on the current buffer by hand NOW type C-x # b.
To run automatically AT EXPORT, just run org-mode export. The hook should fire.
Code
ifdef keybindings and function definitions
; May need to remap
;
; Getting this error as of Emacs 25
; Debugger entered--Lisp error: (error "Key sequence C-x # i starts with non-prefix key C-x #")
;
;(global-set-key (kbd "C-x # i") 'ifdef-ifdef)
;(global-set-key (kbd "C-x # d") 'ifdef-define)
;(global-set-key (kbd "C-x # b") 'ifdef-buffer)
; define global config things for ifdef.
; I'm pretty sure global setq is not the right way...
; set one of these
(setq ifdef-delete-chunks t) ; delete non-matching chunks
(setq ifdef-comment-chunks nil) ; delete non-matching chunks
(setq comment-start "#")
(defun my-text-mode-hook ()
(setq comment-start "#")
; (message "my-text-mode-hook ran.")
)
(defun my-ifdef-hook (backend)
"Apply cpp(1) style ifdefs to buffer before org-mode export."
(ifdef-org-export-hook))
(add-hook 'org-export-before-parsing-hook 'my-ifdef-hook)
(add-hook 'text-mode-hook 'my-text-mode-hook)
(defun ifdef-org-export-hook ()
"Export hook to apply #ifdef logic to buffer during org-mode export"
(interactive)
(setq ifdef-delete-chunks t) ; delete non-matching chunks
(ifdef-buffer)
(ifdef-delete-all-ifdef-lines)
)
(defun ifdef-buffer ()
"Apply cpp-like #ifdef processing to current buffer."
(interactive)
(ifdef-define)
(goto-char (point-min))
(while (ifdef-ifdef) nil)
(ifdef-delete-all-ifdef-lines)
)
(defun ifdef-delete-all-ifdef-lines ()
"Delete all #define, #ifdef, and #endif lines in the current buffer"
(interactive)
(goto-char (point-min))
(while (re-search-forward "^\\s\-\*#\\(ifdef\\|define\\|endif\\)" nil t)
(setq pos1 (line-beginning-position) )
(forward-line 1)
(beginning-of-line)
(setq pos2 (line-beginning-position) )
(delete-region pos1 pos2)
)
)
(defun ifdef-define ()
"Find #ifdef FOO. (setq ifdef-condition FOO). FOO can be an elisp regexp.
e.g. #define \(interesting\|contributions\)"
(interactive)
(setq ifdef-condition nil)
(let ((case-fold-search t))
(save-excursion
(goto-char (point-min))
; first #define wins
(if (search-forward-regexp "^\\s\-\*\\(#define\\) \\(.*$\\)" nil t) (setq ifdef-condition (match-string 2)))
) ; save-excursion
) ;let
(message (concat (concat "ifdef-condition is \"" ifdef-condition) "\""))
ifdef-condition
)
(defun ifdef-ifdef ()
"Delete the next non-matching #ifdef section.
Find ifdef FOO. Cut it out if conditional not defined.
Return t if #ifdef section found (matching or not), nil if not found or no pattern."
(interactive)
(catch 'exit
; (message "ifdef-ifdef")
(let ((case-fold-search t))
(if (boundp 'ifdef-condition)
(progn ; true
(setq ifdef-look-for-this (concat "#ifdef " ifdef-condition))
; (message (concat "ifdef-look-for-this " ifdef-look-for-this))
)
(progn ; false
(message "ifdef-condition not defined")
(throw 'exit nil)
)
)
(setq ifdef-found-ifdef-section nil)
; (message "ifdef-ifdef continue")
(let (beg end (cnt 1) ifdefChunk)
; (save-excursion
(progn
; (message "ifdef-ifdef looking for chunk to delete")
(when (re-search-forward
"^\\s\-\*#ifdef" nil t)
(setq beg (match-beginning 0))
(while (re-search-forward "^\\s\-\*#endif" nil t)
(setq ifdef-chunk (buffer-substring beg (point)))
; (message (concat "ifdef-chunk-START>" ifdef-chunk "<ifdef-chunk-END"))
; (message (concat "ifdef-look-for-this " ifdef-look-for-this))
(setq ifdef-found-ifdef-section t)
(setq ifdef-delete-or-comment-this-chunk nil)
(when (not (string-match ifdef-look-for-this ifdef-chunk))
(setq ifdef-delete-or-comment-this-chunk t))
; (message "ifdef-delete-or-comment-this-chunk")
(if ifdef-delete-or-comment-this-chunk
(if ifdef-delete-chunks ; if delete-chunks
(progn ; if delete chunks
; (message "deleting chunk")
(delete-region beg (point))
; now get rid of any resulting blank lines
(setq ifdef-this-line-is-blank (looking-at "[ \t]*$"))
(setq ifdef-this-line-is-blank t)
(if ifdef-this-line-is-blank
(delete-blank-lines); collapse surrounding bank lines to one
)
)
(if ifdef-comment-chunks ; else if comment chunks
(progn
(comment-region beg (point))
)
) ; if commenting this chunk
) ; if deleting this chunk
) ; if commenting or deleting this chunk
(throw 'exit ifdef-found-ifdef-section)))
nil)))))
ifdef-ifdef
Some sample text
#deFine \(ALICE\|LARRY\) The start of the story is the same. #iFdef ALICE Alice is special, this message is just for her. #endif #ifdef BOB Bob gets a different story #endif #ifdef ALiCE For Alice, the story continues. #endif #ifdef BOB but Bob is left in the dark. #endif #ifdef LARRY Larry Boy. Lean and mean, green machine, outta sight, DYN-O-MITE !!! Lorum ipsum. Foo. #endif
To Do List
Clean up symbols
-
Make everything ifdef-
-
Avoid globals (setq) whehn not neede
Check logic
-
correct placement after ifdef-ifdef ?
Think about name of ifdef-cut
-
should it be something like ifdef-ifdef ?
Think about doing it without regexps
-
narrow-to-region
-
see Le Wang's reply to my post on G++ https://github.com/lewang/ws-butler/blob/master/ws-butler.el#L109
Inhibit ifdef expansoin of example above on export
-
It would be more useful as an example if ifdef left it alone
-
Probably a conditional in the export hook. Look for this file name and skip ifdef processing, or find a way to quote the
TODO Seems to only work with one #define, fix this
TODO Add #else or #ifndef
Test
This is some text
foo - should see this
bar - should see this too, but seems not to work.