branch: externals/easy-escape
commit 8623aa9d715fe7677ea24d7164ea6e4ecdb3e65b
Author: Clément Pit--Claudel <clement.pitclau...@live.com>
Commit: Clément Pit--Claudel <clement.pitclau...@live.com>
Hide backslashes before '(', ')', and '|'
---
README.md | 18 ++----------
easy-escape.el | 86 ++++++++++++++++++++++++++++++++++++++--------------------
2 files changed, 60 insertions(+), 44 deletions(-)
diff --git a/README.md b/README.md
index f0c79cd..9214fae 100644
--- a/README.md
+++ b/README.md
@@ -2,26 +2,14 @@
-`easy-escape-minor-mode` composes double backslashes (escape characters) into
single backslashes, and highlights them to improve readability. The underlying
buffer text is not modified.
+`easy-escape-minor-mode` uses syntax highlighting and composition to make
ELisp regular expressions more readable. More precisely, it hides double
backslashes preceding regexp specials (`()|`), composes other double
backslashes into single ones, and applies a special face to each. The
underlying buffer text is not modified.
-The default is to use a single \ character instead of two, but the character
used and its color can be customized using `easy-escape-face` and
`easy-escape-character`.
-
-## Screenshots
-
-### Using a custom color
-
-
-
-### Using a custom character
-
-
+The default is to use a single \ character instead of two, and to hide
backslashes preceding parentheses or `|`. The escape character and its color
can be customized using `easy-escape-face` and `easy-escape-character` (which
see), and backslashes before `()|` can be shown by disabling
`easy-escape-hide-escapes-before-delimiters`.
## Setup
### MELPA (preferred)
-This will be valid if the package gets accepted on MELPA:
-
1. Setup [MELPA](http://melpa.org/#/getting-started) if you haven't yet
In your `.emacs`, add these three lines:
@@ -34,7 +22,7 @@ This will be valid if the package gets accepted on MELPA:
2. Install the package: `M-x package-install RET easy-escape RET`
-3. Enable `easy-escape-minor-mode` in lisp buffers:
+3. Enable `easy-escape-minor-mode` in Lisp buffers:
```elisp
;; Replace 'lisp-mode-hook with 'prog-mode-hook to enable everywhere
diff --git a/easy-escape.el b/easy-escape.el
index 9b1ca00..801b0f6 100644
--- a/easy-escape.el
+++ b/easy-escape.el
@@ -21,20 +21,25 @@
;;; Commentary:
-;; `easy-escape-minor-mode' composes double backslashes (escape characters)
into
-;; single backslashes, and highlights them to improve readability.
+;; `easy-escape-minor-mode' uses syntax highlighting and composition to make
ELisp regular
+;; expressions more readable. More precisely, it hides double backslashes
+;; preceding regexp specials (`()|'), composes other double backslashes into
+;; single ones, and applies a special face to each. The underlying buffer text
+;; is not modified.
;;
-;; For example, `easy-escape` displays "\\(?:\\_<\\\\newcommand\\_>\\s-*\\)?"
-;; as "\(?:\_<\\newcommand\_>\s-*\)?". The underlying text is not modified.
+;; For example, `easy-escape` prettifies this:
+;; "\\(?:\\_<\\\\newcommand\\_>\\s-*\\)?"
+;; into this (`^' indicates a different color):
+;; "(?:\_<\\newcommand\_>\s-*)?".
+;; ^ ^
;;
-;; The default it to use a single \ character instead of two, but the character
-;; used and its color can be customized using `easy-escape-face' and
-;; `easy-escape-character' (which see).
+;; The default is to use a single \ character instead of two, and to hide
+;; backslashes preceding parentheses or `|'. The escape character and its
color
+;; can be customized using `easy-escape-face' and `easy-escape-character'
(which see), and backslashes
+;; before ()| can be shown by disabling
`easy-escape-hide-escapes-before-delimiters'.
;;
;; Suggested setup:
;; (add-hook 'lisp-mode-hook 'easy-escape-minor-mode)
-;; or
-;; (add-hook 'prog-mode-hook 'easy-escape-minor-mode)
;;
;; NOTE: If you find the distinction between the fontified double-slash and the
;; single slash too subtle, try the following:
@@ -55,6 +60,11 @@
"Face used to highlight \\\\ in strings"
:group 'easy-escape)
+(defface easy-escape-delimiter-face
+ '((t :weight bold :slant normal :inherit font-lock-warning-face))
+ "Face used to highlight groups and alternations in strings"
+ :group 'easy-escape)
+
(defcustom easy-escape-character ?\\
"Character by which \\\\ is replaced when `easy-escape-minor-mode' is active.
Good candidates include the following:
@@ -68,31 +78,48 @@ Good candidates include the following:
⦥ MATHEMATICAL REVERSED ANGLE WITH UNDERBAR (typed as '?⦥')
⦣ MATHEMATICAL REVERSED ANGLE (typed as '?⦣')
⧹ BIG REVERSE SOLIDUS (typed as '?⧹')
-Most of these characters require non-standard fonts to display properly,
however."
+Most of these characters require non-standard fonts to display properly,
+however."
:group 'easy-escape)
-(defconst easy-escape--keywords
- '((easy-escape--mark-escapes (0 (easy-escape--compose (match-beginning 0)))
- (0 'easy-escape-face append)))
- "Font-lock keyword list used internally.")
+(defcustom easy-escape-hide-escapes-before-delimiters t
+ "Whether to hide \\\\ when it precedes one of `(', `|', and `)'."
+ :group 'easy-escape
+ :type 'boolean)
(defun easy-escape--in-string-p (pos)
"Indicate whether POS is inside of a string."
(let ((face (get-text-property pos 'face)))
- (or (eq 'font-lock-string-face face)
- (and (listp face) (memq 'font-lock-string-face face)))))
+ (or (eq 'font-lock-doc-face face)
+ (eq 'font-lock-string-face face)
+ (and (listp face) (or (memq 'font-lock-doc-face face)
+ (memq 'font-lock-string-face face))))))
-(defun easy-escape--mark-escapes (limit)
- "Position point at end of next \\\\, and set match data.
-Search ends at LIMIT."
+(defun easy-escape--mark-in-string (re lim)
+ "Find next match for RE before LIM that falls in a string."
(catch 'found
- (while (re-search-forward "\\(\\\\\\\\\\)" limit t)
+ (while (re-search-forward re lim t)
(when (easy-escape--in-string-p (match-beginning 0))
(throw 'found t)))))
-(defun easy-escape--compose (start)
- "Compose characters from START to (+ 2 START) into `easy-escape-character'."
- (compose-region start (+ 2 start) easy-escape-character))
+(defun easy-escape--mark-escapes (limit)
+ "Search for \\\\ before LIMIT."
+ (easy-escape--mark-in-string "\\(\\\\\\\\\\)" limit))
+
+(defun easy-escape--mark-delims (limit)
+ "Search for a delimiter or alternation before LIMIT."
+ (easy-escape--mark-in-string "\\(\\\\\\\\\\)\\([()|]\\)" limit))
+
+(defun easy-escape--compose (n char)
+ "Compose match group N into CHAR."
+ (compose-region (match-beginning n) (match-end n) char))
+
+(defconst easy-escape--keywords
+ '((easy-escape--mark-escapes
+ (0 (progn (easy-escape--compose 0 easy-escape-character)
'easy-escape-face) prepend))
+ (easy-escape--mark-delims
+ (0 (progn (easy-escape--compose 0 (char-after (match-beginning 2)))
'easy-escape-delimiter-face) prepend)))
+ "Font-lock keyword list used internally.")
;;;###autoload
(define-minor-mode easy-escape-minor-mode
@@ -108,12 +135,13 @@ and the single slash too subtle, try the following:
* Set `easy-escape-character' to a different character."
:lighter " ez-esc"
:group 'easy-escape
- (if easy-escape-minor-mode
- (progn (font-lock-add-keywords nil easy-escape--keywords)
- (add-to-list (make-local-variable 'font-lock-extra-managed-props)
'composition))
- (font-lock-remove-keywords nil easy-escape--keywords))
- (if (>= emacs-major-version 25)
- (font-lock-flush)
+ (cond
+ (easy-escape-minor-mode
+ (font-lock-add-keywords nil easy-escape--keywords)
+ (make-local-variable 'font-lock-extra-managed-props)
+ (add-to-list 'font-lock-extra-managed-props 'composition))
+ (t (font-lock-remove-keywords nil easy-escape--keywords)))
+ (if (>= emacs-major-version 25) (font-lock-flush)
(with-no-warnings (font-lock-fontify-buffer))))
(provide 'easy-escape)
