(class, SS.foldr (op::) [] values) :: out)
[] classes
+fun users () = SM.foldri (fn (user, _, ls) => user :: ls) [] (!acl)
+
fun whoHas {class, value} =
SM.foldri (fn (user, classes, users) =>
case SM.find (classes, class) of
NONE => SS.empty
| SOME values => values
+fun rmuser user =
+ (acl := #1 (SM.remove (!acl, user)))
+ handle NotFound => ()
+
fun grant {user, class, value} =
let
val classes = Option.getOpt (SM.find (!acl, user), SM.empty)
SS.delete (values, value)
else
values
+
+ val classes = if SS.isEmpty values then
+ (#1 (SM.remove (classes, class)))
+ handle NotFound => classes
+ else
+ SM.insert (classes, class, values)
in
- acl := SM.insert (!acl, user,
- SM.insert (classes, class,
- values))
+ if SM.numItems classes = 0 then
+ (acl := #1 (SM.remove (!acl, user)))
+ handle NotFound => ()
+ else
+ acl := SM.insert (!acl, user, classes)
end
+fun revokeFromAll {class, value} =
+ acl := SM.map (fn classes =>
+ case SM.find (classes, class) of
+ NONE => classes
+ | SOME values =>
+ ((SM.insert (classes, class, SS.delete (values, value)))
+ handle NotFound => classes)) (!acl)
+
fun read fname =
let
val inf = TextIO.openIn fname