Support for external help functions (and application to PLT).

4 files changed, 48 insertions, 18 deletions

diff --git a/elisp/geiser-doc.el b/elisp/geiser-doc.el
index 60800f4..2fc9f69 100644
--- a/elisp/geiser-doc.el
+++ b/elisp/geiser-doc.el
@@ -157,6 +157,13 @@
 
 ;;; Commands:
 
+(make-variable-buffer-local
+ (defvar geiser-doc--external-help-function nil))
+
+(defun geiser-doc--external-help (symbol module)
+  (and geiser-doc--external-help-function
+       (funcall geiser-doc--external-help-function symbol module)))
+
 (defun geiser-doc--get-docstring (symbol module)
   (geiser-eval--send/result `(:eval ((:ge symbol-documentation) ',symbol) ,module)))
 
@@ -164,21 +171,22 @@
   (geiser-eval--send/result `(:eval ((:ge module-children) (:module ,module)))))
 
 (defun geiser-doc-symbol (symbol &optional module impl)
-  (let* ((module (or module (geiser-eval--get-module)))
-         (impl (or impl geiser-impl--implementation))
-         (ds (geiser-doc--get-docstring symbol module)))
-    (if (or (not ds) (not (listp ds)))
-        (message "No documentation available for '%s'" symbol)
-      (geiser-doc--with-buffer
-       (erase-buffer)
-       (geiser-doc--insert-title (cdr (assoc 'signature ds)))
-       (newline)
-       (insert (or (cdr (assoc 'docstring ds)) ""))
-       (goto-line (point-min))
-       (setq geiser-doc--buffer-link
-             (geiser-doc--history-push
-              (geiser-doc--make-link symbol module impl))))
-      (geiser-doc--pop-to-buffer))))
+  (let ((module (or module (geiser-eval--get-module))))
+    (unless (geiser-doc--external-help symbol module)
+      (let ((impl (or impl geiser-impl--implementation))
+            (ds (geiser-doc--get-docstring symbol module)))
+        (if (or (not ds) (not (listp ds)))
+            (message "No documentation available for '%s'" symbol)
+          (geiser-doc--with-buffer
+            (erase-buffer)
+            (geiser-doc--insert-title (cdr (assoc 'signature ds)))
+            (newline)
+            (insert (or (cdr (assoc 'docstring ds)) ""))
+            (goto-line (point-min))
+            (setq geiser-doc--buffer-link
+                  (geiser-doc--history-push
+                   (geiser-doc--make-link symbol module impl))))
+          (geiser-doc--pop-to-buffer))))))
 
 (defun geiser-doc-symbol-at-point (&optional arg)
   "Get docstring for symbol at point.
diff --git a/elisp/geiser-impl.el b/elisp/geiser-impl.el
index 312ace9..ac6c2b9 100644
--- a/elisp/geiser-impl.el
+++ b/elisp/geiser-impl.el
@@ -27,6 +27,7 @@
 
 (require 'geiser-eval)
 (require 'geiser-base)
+(require 'geiser-doc)
 
 
 ;;; Customization:
@@ -120,10 +121,16 @@
 (defsubst geiser-impl--geiser-procedure-function (impl)
   (geiser-impl--sym impl "geiser-procedure"))
 
+(defsubst geiser-impl--external-help-function (impl)
+  (let ((f (geiser-impl--sym impl "external-help")))
+    (and (fboundp f) f)))
+
 (defun geiser-impl--install-eval (impl)
   (setq geiser-eval--get-module-function (geiser-impl--module-function impl))
   (setq geiser-eval--geiser-procedure-function
-        (geiser-impl--geiser-procedure-function impl)))
+        (geiser-impl--geiser-procedure-function impl))
+  (setq geiser-doc--external-help-function
+        (geiser-impl--external-help-function impl)))
 
 
 ;;; Evaluating Elisp in a given implementation context:
@@ -132,7 +139,9 @@
   (let ((geiser-impl--implementation imp)
         (geiser-eval--get-module-function (geiser-impl--module-function imp))
         (geiser-eval--geiser-procedure-function
-         (geiser-impl--geiser-procedure-function imp)))
+         (geiser-impl--geiser-procedure-function imp))
+        (geiser-doc--external-help-function
+         (geiser-impl--external-help-function imp)))
     (funcall thunk)))
 
 (put 'with--geiser-implementation 'lisp-indent-function 1)
diff --git a/elisp/geiser-plt.el b/elisp/geiser-plt.el
index aa9a901..77551c6 100644
--- a/elisp/geiser-plt.el
+++ b/elisp/geiser-plt.el
@@ -25,6 +25,7 @@
 ;;; Code:
 
 (require 'geiser-impl)
+(require 'geiser-eval)
 (require 'geiser-syntax)
 (require 'geiser-custom)
 (require 'geiser-base)
@@ -101,6 +102,12 @@ This function uses `geiser-plt-init-file' if it exists."
         (t module)))
 
 
+;;; External help
+(defun geiser-plt-external-help (symbol module)
+  (message "Requesting help for '%s'..." symbol)
+  (geiser-eval--send/wait `(:eval (help ,symbol) 'geiser)))
+
+
 ;;; Trying to ascertain whether a buffer is mzscheme scheme:
 
 (defun geiser-plt-guess ()
diff --git a/elisp/geiser.el b/elisp/geiser.el
index 4ccc1e1..146f421 100644
--- a/elisp/geiser.el
+++ b/elisp/geiser.el
@@ -60,6 +60,12 @@
 (autoload 'switch-to-guile "geiser-guile.el"
   "Start a Geiser Guile REPL, or switch to a running one." t)
 
+(autoload 'run-plt "geiser-plt.el"
+  "Start a Geiser MzScheme REPL, or switch to a running one." t)
+
+(autoload 'switch-to-plt "geiser-guile.el"
+  "Start a Geiser MzScheme REPL, or switch to a running one." t)
+
 (autoload 'geiser-mode "geiser-mode.el"
   "Minor mode adding Geiser REPL interaction to Scheme buffers." t)
 
@@ -102,6 +108,7 @@
   (quote '(
            geiser-mode
            geiser-repl
+           geiser-impl
            geiser-doc
            geiser-xref
            geiser-edit
@@ -109,7 +116,6 @@
            geiser-autodoc
            geiser-compile
            geiser-debug
-           geiser-impl
            geiser-eval
            geiser-connection
            geiser-syntax