tidying

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/zcoord/zcoord.rs b/zcoord/zcoord.rs
index 52813f7e1db2f18cf501456e1143fe4865056bf4..aabc2cb76d5937d1a07f4caf37a3d98daad00cbe 100644 (file)
--- a/zcoord/zcoord.rs
+++ b/zcoord/zcoord.rs
@@ -158,14 +158,14 @@ impl AddSubOffset for AddSubInc {
 
 struct AddSubDec;
 impl AddSubOffset for AddSubDec {
-  fn init_delta(&self) -> LimbVal { Wrapping(DELTA.0.wrapping_neg()) }
+  fn init_delta(&self) -> LimbVal { -DELTA }
   const CARRY_DELTA : LimbVal = Wrapping(ONE  .0.wrapping_neg());
   const NEW_LIMBS   : LimbVal = LIMB_MASK;
   #[throws(as Option)]
   fn check_underflow(_: &Mutable, i: usize, nv: LimbVal) {
     if i == 0 && nv == ZERO { throw!() }
   }
-  fn final_undo_delta() -> LimbVal { ZERO - DELTA + ONE }
+  fn final_undo_delta() -> LimbVal { -DELTA + ONE }
 }
 
 impl Mutable {