tuples: convert tuple generation to seq_build.

* lib.c (tuples_func): Replace list accumulation
with make_like with seq_build.

* tests/012/seq.tl: Fix one test case here which no
longer errors out. It produces a tuple which is not
a string, due to the inclusion of a non-character
object.

2 files changed, 8 insertions, 5 deletions

diff --git a/lib.c b/lib.c
index a0c26ff0..11c579c2 100644
--- a/lib.c
+++ b/lib.c
@@ -3785,24 +3785,27 @@ val lazy_flatcar(val tree)
 
 static val tuples_func(val n, val lcons)
 {
-  list_collect_decl (out, ptail);
+  seq_build_t bu;
   us_cons_bind (iter_in, fill, lcons);
   val iter = iter_in;
   val count;
 
+  seq_build_init(lit("tuples"), &bu, iter);
+
   for (count = n; count != zero && iter_more(iter);
        count = minus(count, one), iter = iter_step(iter))
-    ptail = list_collect(ptail, iter_item(iter));
+    seq_add(&bu, iter_item(iter));
 
   if (!missingp(fill))
     for (; gt(count, zero); count = minus(count, one))
-      ptail = list_collect(ptail, fill);
+      seq_add(&bu, fill);
 
   if (iter_more(iter))
     us_rplacd(lcons, make_lazy_cons_car_cdr(us_lcons_fun(lcons), iter, fill));
   else
     us_rplacd(lcons, nil);
-  us_rplaca(lcons, make_like(out, iter_in));
+
+  us_rplaca(lcons, seq_finish(&bu));
 
   return nil;
 }
diff --git a/tests/012/seq.tl b/tests/012/seq.tl
index 407af84a..144c6971 100644
--- a/tests/012/seq.tl
+++ b/tests/012/seq.tl
@@ -263,7 +263,7 @@
   list)
 
 (test
-  (lforce (tuples 2 "abc" 3)) :error)
+  (lforce (tuples 2 "abc" 3)) ("ab" (#\c 3)))
 
 (test
   (take 3 (tuples 3 (range 0))) ((0 1 2) (3 4 5) (6 7 8)))