Fix Typo

hol/exps.hl

@@ -59,7 +59,7 @@ let eval_err = new_recursive_definition exp_REC
   Define real evaluation as stated above:
 *)
 let eval_real = define
-  `eval_real (e:(real)exp) (env:num->real) = eval_err e (\x. &0) (\x. &0)`;;
+  `eval_real (e:(real)exp) (env:num->real) = eval_err e (\x. &0) (\x. &0) env`;;
 
 (*
   float evaluation is non-deterministic, since the perturbation is existencially quantified