1 files changed, 62 insertions, 0 deletions
diff --git a/vere/pkg/noun/jets/b/skid.c b/vere/pkg/noun/jets/b/skid.c
new file mode 100644
index 0000000..8d0d7ef
--- /dev/null
+++ b/vere/pkg/noun/jets/b/skid.c
@@ -0,0 +1,62 @@
+/// @file
+
+#include "jets/q.h"
+#include "jets/w.h"
+
+#include "noun.h"
+
+u3_noun
+u3qb_skid(u3_noun a, u3_noun b)
+{
+  u3_noun l, r;
+  u3_noun* lef = &l;
+  u3_noun* rig = &r;
+
+  if ( u3_nul != a) {
+    u3_noun   i, t;
+    u3_noun*   hed;
+    u3_noun*   tel;
+    u3j_site sit_u;
+    u3j_gate_prep(&sit_u, u3k(b));
+    u3k(a);
+
+    do {
+      i = u3h(a);
+
+      switch ( u3j_gate_slam(&sit_u, u3k(i)) ) {
+        case c3y: {
+          *lef = u3i_defcons(&hed, &tel);
+          *hed = u3k(i);
+          lef  = tel;
+        } break;
+
+        case c3n: {
+          *rig = u3i_defcons(&hed, &tel);
+          *hed = u3k(i);
+          rig  = tel;
+        } break;
+
+        default: u3m_bail(c3__exit);
+      }
+
+      t = u3k(u3t(a));
+      u3z(a), a = t;
+    }
+    while ( u3_nul != a );
+
+    u3j_gate_lose(&sit_u);
+  }
+
+  *lef = u3_nul;
+  *rig = u3_nul;
+
+  return u3nc(l, r);
+}
+
+u3_noun
+u3wb_skid(u3_noun cor)
+{
+  u3_noun a, b;
+  u3x_mean(cor, u3x_sam_2, &a, u3x_sam_3, &b, 0);
+  return u3qb_skid(a, b);
+}