| type pos = {file : string; line : int; column : int} | |
| type region = {left : pos; right : pos} | |
| type 'a phrase = {at : region; it : 'a} | |
| val no_pos : pos | |
| val no_region : region | |
| val string_of_pos : pos -> string | |
| val string_of_region : region -> string | |
| val (@@) : 'a -> region -> 'a phrase |