(py|rb)env version in modeline + define-builder macro

core/lib/defuns-spaceline.el

@@ -0,0 +1,13 @@
+;;; defuns-spaceline.el
+
+;;;###autoload
+(defun narf|spaceline-env-update ()
+  (when narf--env-command
+    (let* ((command (format "cd '%s' && %s" (narf/project-root) narf--env-command))
+           (s (shell-command-to-string command)))
+      (setq narf--env-version (if (string-match "[ \t\n\r]+\\'" s)
+                                  (replace-match "" t t s)
+                                s)))))
+
+(provide 'defuns-spaceline)
+;;; defuns-spaceline.el ends here

core/lib/macros-quickrun.el

@@ -1,7 +1,7 @@
 ;;; macros-quickrun.el
 
 ;;;###autoload
-(defmacro build-for! (mode command &optional build-file)
+(defmacro define-builder! (mode command &optional build-file)
   "Register major/minor MODE with build COMMAND. If FILES are provided, do an
 additional check to make sure they exist in the project root."
   `(add-hook! ,mode

core/lib/macros-spaceline.el

@@ -0,0 +1,10 @@
+;;; defuns-spaceline.el
+
+;;;###autoload
+(defmacro define-env-command! (mode command)
+  (add-hook! (focus-in find-file) 'narf|spaceline-env-update)
+  `(add-hook ',(intern (format "%s-hook" (symbol-name mode)))
+             (lambda () (setq narf--env-command ,command))))
+
+(provide 'defuns-spaceline)
+;;; defuns-spaceline.el ends here