From b81b6106f9feda8f3bce9eca3173560778c336fb Mon Sep 17 00:00:00 2001 From: Magnus Henoch Date: Wed, 15 Sep 2010 15:24:52 +0100 Subject: Emacs erlang-mode: fix syntax highlighting of $ in two cases A string whose last character is a dollar sign used to make the syntax highlighter believe that the string never ends, breaking highlighting of following code: -vsn("$Revision: 42 $"). And the double quote as a character constant with a (superfluous) backslash used to make the syntax highlighter believe that a new string started: foo() -> $\". This change fixes both problems by adding two regexps to font-lock-syntactic-keywords in erlang-font-lock-init. One case that is still broken is when a multi-line string ends with a dollar sign: bar() -> "This multi-line string ends with a $". baz() -> this_gets_incorrectly_highlighted. --- lib/tools/emacs/erlang.el | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) (limited to 'lib/tools') diff --git a/lib/tools/emacs/erlang.el b/lib/tools/emacs/erlang.el index 91acfdf2b6..ed825a298f 100644 --- a/lib/tools/emacs/erlang.el +++ b/lib/tools/emacs/erlang.el @@ -1481,7 +1481,23 @@ Other commands: erlang-font-lock-keywords-3 erlang-font-lock-keywords-4) nil nil ((?_ . "w")) erlang-beginning-of-clause - (font-lock-mark-block-function . erlang-mark-clause)))) + (font-lock-mark-block-function . erlang-mark-clause) + (font-lock-syntactic-keywords + ;; A dollar sign right before the double quote that ends a + ;; string is not a character escape. + ;; + ;; And a "string" has with a double quote not escaped by a + ;; dollar sign, any number of non-backslash non-newline + ;; characters or escaped backslashes, a dollar sign + ;; (otherwise we wouldn't care) and a double quote. This + ;; doesn't match multi-line strings, but this is probably + ;; the best we can get, since while font-locking we don't + ;; know whether matching started inside a string: limiting + ;; search to a single line keeps things sane. + . (("\\(?:^\\|[^$]\\)\"\\(?:[^\"\n]\\|\\\\\"\\)*\\(\\$\\)\"" 1 "w") + ;; And the dollar sign in $\" escapes two characters, not + ;; just one. + ("\\(\\$\\)\\\\\\\"" 1 "'")))))) -- cgit v1.2.3