--- a/src/Pure/RAW/single_assignment_polyml.ML Thu Mar 03 17:03:09 2016 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,35 +0,0 @@
-(* Title: Pure/RAW/single_assignment_polyml.ML
- Author: Makarius
-
-References with single assignment. Unsynchronized! Emulates
-structure SingleAssignment from Poly/ML 5.4.
-*)
-
-signature SINGLE_ASSIGNMENT =
-sig
- type 'a saref
- exception Locked
- val saref: unit -> 'a saref
- val savalue: 'a saref -> 'a option
- val saset: 'a saref * 'a -> unit
-end;
-
-structure SingleAssignment: SINGLE_ASSIGNMENT =
-struct
-
-exception Locked;
-
-abstype 'a saref = SARef of 'a option ref
-with
-
-fun saref () = SARef (ref NONE);
-
-fun savalue (SARef r) = ! r;
-
-fun saset (SARef (r as ref NONE), x) =
- (r := SOME x; RunCall.run_call1 RuntimeCalls.POLY_SYS_lockseg r)
- | saset _ = raise Locked;
-
-end;
-
-end;