Add RandomAccessMemory class for in-memory binary operations

dart/lib/structures.dart

@@ -0,0 +1,48 @@
+
+enum SweepstorePrimitives {
+
+  POINTER       (8),
+  ADDRESS_TABLE (-1);
+
+  final int size;
+  final bool arrayType;
+  const SweepstorePrimitives(this.size, {
+    this.arrayType = false
+  });
+
+}
+
+class SweepstorePointer {
+
+  static const SweepstorePointer nullptr = SweepstorePointer(-1);
+
+  final int address;
+
+  const SweepstorePointer(this.address);
+
+  bool get isNull => address == -1;
+
+  operator ==(Object other) {
+    if (identical(this, other)) return true;
+    if (other is! SweepstorePointer) return false;
+    return address == other.address;
+  }
+
+  @override
+  String toString() => '0x${address.toRadixString(16)} ($address)';
+}
+
+enum SweepstoreTicketState {
+  FREE,
+  WAITING,
+  APPROVED,
+  EXECUTING,
+  COMPLETED,
+}
+
+enum SweepstoreTicketOperation {
+  NONE,
+  READ,
+  MODIFY,
+  WRITE,
+}