quasistrings: reduce consing.

Quasistrings compile to code that requires on the sys:fmt-join
function to glue strings together. Rewriting that function to
avoid converting its arguments from struct args * to a list.

* eval.c (fmt_join): Static function removed.

* lib.c (cat_str_measure, cat_str_append): more_p parameter
changed to int type, which better matches the C style Boolean
values it takes.
(fmt_join): New external function.

* lib.h: Declared.

* args.h (args_more_nozap, args_get_nozap): New inline
functions allowing multiple iterations over arguments without
making a copy.

1 files changed, 12 insertions, 0 deletions

diff --git a/args.h b/args.h
index c1455fd6..54c00bf2 100644
--- a/args.h
+++ b/args.h
@@ -130,6 +130,11 @@ INLINE int args_two_more(struct args *args, cnum index)
     cdr(args->list);
 }
 
+INLINE int args_more_nozap(struct args *args, cnum index, val list)
+{
+  return list || index < args->fill;
+}
+
 void args_normalize_exact(struct args *args, cnum fill);
 void args_normalize_least(struct args *args, cnum fill);
 void args_normalize_fill(struct args *args, cnum minfill, cnum maxfill);
@@ -173,6 +178,13 @@ INLINE val args_get(struct args *args, cnum *arg_index)
   return pop(&args->list);
 }
 
+INLINE val args_get_nozap(struct args *args, cnum *arg_index, val *list)
+{
+  if (*arg_index < args->fill)
+    return args->arg[(*arg_index)++];
+  return pop(list);
+}
+
 INLINE cnum args_count(struct args *args)
 {
   return args->fill + c_num(length_list(args->list));