diff --git a/ranges/ptr_arith.nim b/ranges/ptr_arith.nim
new file mode 100644
index 0000000..8f6b848
--- /dev/null
+++ b/ranges/ptr_arith.nim
@@ -0,0 +1,5 @@
+proc baseAddr*[T](x: openarray[T]): pointer = cast[pointer](x)
+
+proc shift*(p: pointer, delta: int): pointer =
+  cast[pointer](cast[int](p) + delta)
+