feat(emacs/lean-util.el): add lean-util.el

src/emacs/lean-util.el

@@ -0,0 +1,28 @@
+;; Copyright (c) 2014 Microsoft Corporation. All rights reserved.
+;; Released under Apache 2.0 license as described in the file LICENSE.
+;;
+;; Author: Soonho Kong
+;;
+
+(defmacro lean-get-this-if-true-or-that (this that)
+  `(cond (,this ,this)
+         (t ,that)))
+
+(defun lean-get-rootdir ()
+  (lean-get-this-if-true-or-that
+   lean-rootdir
+   (error "'lean-rootdir' is not defined. Please have\
+(customize-set-variable 'lean-rootdir \"~/work/lean\")\
+in your emacs configuration.\
+Also make sure that your (custom-set-variable ...) comes before\
+(require 'lean-mode).")))
+
+(defun lean-get-executable (exe-name)
+  "Return fullpath of lean executable"
+  (let ((lean-binary-dir-name "bin"))
+    (when lean-rootdir
+      (concat (file-name-as-directory (lean-get-rootdir))
+              (file-name-as-directory "bin")
+              exe-name))))
+
+(provide 'lean-util)