txr: bugfix: repeat not finding Lisp vars in brace.

The following does not work and is fixed here:

  @(output)
  @(repeat)
  @{lisp-expr ...}
  @(end)

When a Lisp expression occurs in a braced expansion
syntax, it is not not traversed to find variables.

* parser.y (extract_vars): Treat the second element of a
sys:var as a Lisp expression, and find variables. Don't do
this in 128 or older compatibility mode, because then that is
a TXR expression.

* y.tab.c.shipped: Regenerated.

2 files changed, 18 insertions, 10 deletions

diff --git a/parser.y b/parser.y
index 409400f0..9c352bba 100644
--- a/parser.y
+++ b/parser.y
@@ -1488,13 +1488,17 @@ static val extract_vars(val output_spec)
   if (consp(output_spec)) {
     val sym = first(output_spec);
     if (sym == var_s) {
-      val name = second(output_spec);
+      val expr = second(output_spec);
       val modifiers = third(output_spec);
 
-      if (bindable(name))
-        tai = list_collect(tai, name);
-      else
-        tai = list_collect_nconc(tai, extract_vars(name));
+      if (bindable(expr)) {
+        tai = list_collect(tai, expr);
+      } else if (opt_compat && opt_compat <= 128) {
+        tai = list_collect_nconc(tai, extract_vars(expr));
+      } else {
+        val frefs = expand_with_free_refs(expr, nil, nil);
+        tai = list_collect_nconc(tai, second(frefs));
+      }
 
       for (; modifiers; modifiers = cdr(modifiers)) {
         val mod = car(modifiers);
diff --git a/y.tab.c.shipped b/y.tab.c.shipped
index 2345cb9a..a148a9b3 100644
--- a/y.tab.c.shipped
+++ b/y.tab.c.shipped
@@ -6767,13 +6767,17 @@ static val extract_vars(val output_spec)
   if (consp(output_spec)) {
     val sym = first(output_spec);
     if (sym == var_s) {
-      val name = second(output_spec);
+      val expr = second(output_spec);
       val modifiers = third(output_spec);
 
-      if (bindable(name))
-        tai = list_collect(tai, name);
-      else
-        tai = list_collect_nconc(tai, extract_vars(name));
+      if (bindable(expr)) {
+        tai = list_collect(tai, expr);
+      } else if (opt_compat && opt_compat <= 128) {
+        tai = list_collect_nconc(tai, extract_vars(expr));
+      } else {
+        val frefs = expand_with_free_refs(expr, nil, nil);
+        tai = list_collect_nconc(tai, second(frefs));
+      }
 
       for (; modifiers; modifiers = cdr(modifiers)) {
         val mod = car(modifiers);