Simplify Coq proof

coq/Expressions.v

@@ -53,7 +53,9 @@ Definition env_ty := nat -> R.
 **)
 Inductive eval_exp (eps:R) (env:env_ty) : (exp R) -> R -> Prop :=
   Var_load x: eval_exp eps env (Var R x) (env x)
-| Param_acc x delta: ((Rabs delta) <= eps)%R -> eval_exp eps env (Param R x) (perturb (env x) delta)
+| Param_acc x delta:
+    ((Rabs delta) <= eps)%R ->
+    eval_exp eps env (Param R x) (perturb (env x) delta)
 | Const_dist n delta:
     Rle (Rabs delta) eps ->
     eval_exp eps env (Const n) (perturb n delta)
@@ -62,10 +64,6 @@ Inductive eval_exp (eps:R) (env:env_ty) : (exp R) -> R -> Prop :=
                 eval_exp eps env e1 v1 ->
                 eval_exp eps env e2 v2 ->
                 eval_exp eps env (Binop op e1 e2) (perturb (eval_binop op v1 v2) delta).
-(**
-  Define real evaluation as stated above:
- **)
-Definition is_real_value (e:exp R) (env:env_ty) (v:R) := eval_exp R0 env e v.
 (**
   Prove that using eps = 0 makes the evaluation deterministic
  **)
@@ -144,7 +142,7 @@ Proof.
   inversion eval_float; subst.
   unfold perturb; simpl.
   rewrite Rabs_err_simpl.
-  repeat rewrite Rabs_mult.
+  rewrite Rabs_mult.
   apply Rmult_le_compat_l; [apply Rabs_pos | auto].
 Qed.