Copy lazy strings without forcing.

* lib.c (copy_lazy_str): New static function.
(copy_str): Use copy_lazy_str to copy lazy strings.

* txr.1: Documentation added under copy-str.

1 files changed, 16 insertions, 1 deletions

diff --git a/lib.c b/lib.c
index c54924fe..87abf0b9 100644
--- a/lib.c
+++ b/lib.c
@@ -2543,9 +2543,13 @@ val init_str(val str, const wchar_t *data)
   return str;
 }
 
+static val copy_lazy_str(val lstr);
+
 val copy_str(val str)
 {
-  return string(c_str(str));
+  return if3(lazy_stringp(str),
+             copy_lazy_str(str),
+             string(c_str(str)));
 }
 
 val upcase_str(val str)
@@ -5683,6 +5687,17 @@ val lazy_str(val lst, val term, val limit)
   return obj;
 }
 
+static val copy_lazy_str(val lstr)
+{
+  val obj = make_obj();
+  obj->ls.type = LSTR;
+  obj->ls.opts = obj->ls.list = obj->ls.prefix = nil;
+  obj->ls.prefix = copy_str(lstr->ls.prefix);
+  obj->ls.list = lstr->ls.list;
+  obj->ls.opts = lstr->ls.opts;
+  return obj;
+}
+
 val lazy_str_force(val lstr)
 {
   val lim, term;