src/Pure/General/path.scala

   {
     val (prfx, s) = split_path
     prfx + Path.basic(s + "~~")
   }
 
-  def platform_exe: Path =
-    if (Platform.is_windows) ext("exe") else this
+  def exe: Path = ext("exe")
+  def platform_exe: Path = if (Platform.is_windows) exe else this
 
   private val Ext = new Regex("(.*)\\.([^.]*)")
 
   def split_ext: (Path, String) =
   {