Support for implementation-specific font lock keywords

Spinning up from correct fontification of [else in this brave Racket
world.

I'm keeping the list of extra keywords lean and mean, but making it
customizable in both Racket and Guile.

2 files changed, 19 insertions, 1 deletions

diff --git a/elisp/geiser-mode.el b/elisp/geiser-mode.el
index 8f8b7fe..fe7936f 100644
--- a/elisp/geiser-mode.el
+++ b/elisp/geiser-mode.el
@@ -21,6 +21,7 @@
 (require 'geiser-edit)
 (require 'geiser-autodoc)
 (require 'geiser-debug)
+(require 'geiser-syntax)
 (require 'geiser-impl)
 (require 'geiser-eval)
 (require 'geiser-popup)
@@ -244,7 +245,8 @@ interacting with the Geiser REPL is at your disposal.
   (when geiser-mode-autodoc-p
     (geiser-autodoc-mode (if geiser-mode 1 -1)))
   (when geiser-mode-smart-tab-p
-    (geiser-smart-tab-mode (if geiser-mode 1 -1))))
+    (geiser-smart-tab-mode (if geiser-mode 1 -1)))
+  (geiser-syntax--add-kws))
 
 (defun turn-on-geiser-mode ()
   "Enable `geiser-mode' (in a Scheme buffer)."
diff --git a/elisp/geiser-syntax.el b/elisp/geiser-syntax.el
index f134ea4..40f2def 100644
--- a/elisp/geiser-syntax.el
+++ b/elisp/geiser-syntax.el
@@ -85,6 +85,22 @@
  (with-syntax 1))
 
 
+;;; Extra syntax keywords
+(defconst geiser-syntax--keywords
+  '(("\\[\\(else\\)\\>" . 1)
+    ("(\\(parameterize\\)\\>" . 1)))
+
+(font-lock-add-keywords 'scheme-mode geiser-syntax--keywords)
+
+(geiser-impl--define-caller geiser-syntax--impl-kws keywords ()
+  "A variable (or thunk returning a value) giving additional,
+implementation-specific entries for font-lock-keywords.")
+
+(defun geiser-syntax--add-kws ()
+  (let ((kw (geiser-syntax--impl-kws geiser-impl--implementation)))
+    (when kw (font-lock-add-keywords nil kw))))
+
+
 ;;; A simple scheme reader
 
 (defvar geiser-syntax--read/buffer-limit nil)