sig
type param =
value_message * Cil_types.kinstr * callstack * (state * Trace.t)
type result = unit
val extend : (param -> result) -> unit
val extend_once : (param -> result) -> unit
val is_empty : unit -> bool
val clear : unit -> unit
val length : unit -> int
val apply :
Value_messages.value_message * Cil_types.kinstr *
Value_messages.callstack * (Value_messages.state * Trace.t) -> result
end