+=head2 goalloc
+
+Inside goals, you can use C<goalloc> to get a printable source
+location of the goal, ie:
+
+ let goal foo () =
+ printf "%s\n" goalloc
+
+would print:
+
+ File "source.ml", line 2, characters 13-71 (end at line 3, character 23)
+
+Note that the actual string format depends on the internal OCaml
+function C<Loc.to_string> so it might change in future.
+