1 files changed, 42 insertions, 0 deletions
diff --git a/modules/sequence.c b/modules/sequence.c
new file mode 100644
index 0000000..bda80d9
--- /dev/null
+++ b/modules/sequence.c
@@ -0,0 +1,42 @@
+/* Copyright Vladimir Prus 2003. Distributed under the Boost */
+/* Software License, Version 1.0. (See accompanying */
+/* file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) */
+
+#include "../native.h"
+
+# ifndef max
+# define max( a,b ) ((a)>(b)?(a):(b))
+# endif
+
+
+LIST *sequence_select_highest_ranked( PARSE *parse, FRAME *frame )
+{
+   /* Returns all of 'elements' for which corresponding element in parallel */
+   /* list 'rank' is equal to the maximum value in 'rank'.                  */
+
+    LIST* elements = lol_get( frame->args, 0 );    
+    LIST* rank = lol_get( frame->args, 1 );    
+    
+    LIST* result = 0;
+    LIST* tmp;
+    int highest_rank = -1;
+
+    for (tmp = rank; tmp; tmp = tmp->next)
+        highest_rank = max(highest_rank, atoi(tmp->string));
+
+    for (; rank; rank = rank->next, elements = elements->next)
+        if (atoi(rank->string) == highest_rank)
+            result = list_new(result, elements->string);
+
+    return result;
+}
+
+void init_sequence()
+{
+    {
+        char* args[] = { "elements", "*", ":", "rank", "*", 0 };
+        declare_native_rule("sequence", "select-highest-ranked", args, 
+                            sequence_select_highest_ranked, 1);
+    }
+
+}