* eval.c (dwim_loc, dwim_op): Eliminated redundant re-evaluation

of range arguments. They are already evaluated since the cons
expression is evaluates as part of the dwim arglist.
Replaced some open code with function calls to the new listref
and listref_l functions.
(tostring, tostringp): made extern and moved to lib.c.

* lib.c (listref, listref_l): New functions.
(tostring, tostringp): moved here from eval.c.

* lib.h (listref, listref_l, tostring, tostringp): Declared.

* match.c (format_field): Handle index and range references.

* txr.1: Documented new output variable syntax.

1 files changed, 6 insertions, 38 deletions

diff --git a/eval.c b/eval.c
index 613359a4..8d83f37d 100644
--- a/eval.c
+++ b/eval.c
@@ -663,14 +663,11 @@ static val *dwim_loc(val form, val env, val op, val newval)
       val index = first(args);
 
       if (consp(index)) {
-        val from = eval(car(index), env, form);
-        val to = eval(cdr(index), env, form);
-
         if (op != set_s) 
           eval_error(form, lit("[~s ~s]: slice takes only simple assignments"),
                      obj, index, nao);
 
-        replace_vec(obj, from, to, newval);
+        replace_vec(obj, car(index), cdr(index), newval);
         return 0;
       } else {
         return vecref_l(obj, first(args));
@@ -685,15 +682,8 @@ static val *dwim_loc(val form, val env, val op, val newval)
       val index = first(args);
       val cell = obj;
       if (bignump(index) || fixnump(index)) {
-        for (; gt(index, zero); index = minus(index, one))
-          cell = cdr(cell);
-        if (lt(index, zero) || !cell)
-          eval_error(form, lit("[~s ~s]: cannot assign nonexistent location"),
-                     cell, first(args), nao);
-        return car_l(cell);
+        return listref_l(obj, index);
       } else if (consp(index)) {
-        val from = eval(car(index), env, form);
-        val to = eval(cdr(index), env, form);
         val newlist;
         val tempform;
 
@@ -701,7 +691,7 @@ static val *dwim_loc(val form, val env, val op, val newval)
           eval_error(form, lit("[~s ~s]: slice takes only simple assignments"),
                      cell, index, nao);
 
-        newlist = replace_list(obj, from, to, newval);
+        newlist = replace_list(obj, car(index), cdr(index), newval);
         tempform = list(op, second(form), 
                         cons(quote_s, cons(newlist, nil)), nao);
         eval(tempform, env, form);
@@ -947,9 +937,7 @@ static val op_dwim(val form, val env)
       val index = first(args);
 
       if (consp(index)) {
-        val from = eval(car(index), env, form);
-        val to = eval(cdr(index), env, form);
-        return sub_vec(obj, from, to);
+        return sub_vec(obj, car(index), cdr(index));
       } else {
         return vecref(obj, first(args));
       }
@@ -966,15 +954,9 @@ static val op_dwim(val form, val env)
                    obj, index, nao);
 
       if (consp(index)) {
-        val from = eval(car(index), env, form);
-        val to = eval(cdr(index), env, form);
-        return sub_list(obj, from, to);
+        return sub_list(obj, car(index), cdr(index));
       } else {
-        if (lt(index, zero))
-          return nil;
-        for (; gt(index, zero); index = minus(index, one))
-          obj = cdr(obj);
-        return car(obj);
+        return listref(obj, first(args));
       }
     }
   case COBJ:
@@ -1500,20 +1482,6 @@ static val lazy_mappendv(val fun, val list_of_lists)
   return lazy_appendv(lazy_mapcarv(fun, list_of_lists));
 }
 
-static val tostring(val obj)
-{
-  val ss = make_string_output_stream();
-  obj_print(obj, ss);
-  return get_string_from_stream(ss);
-}
-
-static val tostringp(val obj)
-{
-  val ss = make_string_output_stream();
-  obj_pprint(obj, ss);
-  return get_string_from_stream(ss);
-}
-
 static val symbol_function(val sym)
 {
   return lookup_fun(nil, sym);