lang/org: add eval handler

With this, gr and gR will now work in babel blocks to execute a subset
of the block (or the whole thing, if you'd like). Results are displayed
in a popup buffer (or overlay if :tools (eval +overlay) is enabled).

modules/lang/org/autoload/org-babel.el

@@ -0,0 +1,29 @@
+;;; lang/org/autoload/org-babel.el -*- lexical-binding: t; -*-
+
+;;;###autoload
+(defun +org-eval-handler (beg end)
+  "TODO"
+  (save-excursion
+    (if (not (cl-loop for pos in (list beg (point) end)
+                      if (save-excursion (goto-char pos) (org-in-src-block-p t))
+                      return (goto-char pos)))
+        (message "Nothing to evaluate at point")
+      (org-babel-where-is-src-block-head)
+      (let ((beg (max beg (match-beginning 5)))
+            (end (min end (match-end 5)))
+            (major-mode
+             (org-src-get-lang-mode (or (org-eldoc-get-src-lang)
+                                        (user-error "No lang specified for this src block")))))
+        (+eval/region beg end)))))
+
+
+;;
+;;; Hooks
+
+;;;###autoload
+(defun +org-clear-babel-results-h ()
+  "Remove the results block for the org babel block at point."
+  (when (and (org-in-src-block-p t)
+             (org-babel-where-is-src-block-result))
+    (org-babel-remove-result)
+    t))

modules/lang/org/autoload/org.el

@@ -468,14 +468,6 @@ All my (performant) foldings needs are met between this and `org-show-subtree'
           (org-cycle-internal-local)
           t)))))
 
-;;;###autoload
-(defun +org-clear-babel-results-h ()
-  "Remove the results block for the org babel block at point."
-  (when (and (org-in-src-block-p t)
-             (org-babel-where-is-src-block-result))
-    (org-babel-remove-result)
-    t))
-
 ;;;###autoload
 (defun +org-make-last-point-visible-h ()
   "Unfold subtree around point if saveplace places us in a folded region."