1 files changed, 63 insertions, 0 deletions
diff --git a/vere/pkg/noun/jets/c/lsh.c b/vere/pkg/noun/jets/c/lsh.c
new file mode 100644
index 0000000..09a97e6
--- /dev/null
+++ b/vere/pkg/noun/jets/c/lsh.c
@@ -0,0 +1,63 @@
+/// @file
+
+#include "jets/k.h"
+#include "jets/q.h"
+#include "jets/w.h"
+
+#include "noun.h"
+
+u3_noun
+u3qc_lsh(u3_atom a,
+         u3_atom b,
+         u3_atom c)
+{
+  if ( !_(u3a_is_cat(a)) || (a >= 32) ) {
+    return u3m_bail(c3__fail);
+  }
+  else if ( !_(u3a_is_cat(b)) ) {
+    return u3m_bail(c3__fail);
+  }
+  else {
+    c3_g a_g   = a;
+    c3_w b_w   = b;
+    c3_w len_w = u3r_met(a_g, c);
+
+    if ( 0 == len_w ) {
+      return 0;
+    }
+    else if ( (b_w + len_w) < len_w ) {
+      return u3m_bail(c3__exit);
+    }
+    else {
+      u3i_slab sab_u;
+      u3i_slab_init(&sab_u, a_g, (b_w + len_w));
+
+      u3r_chop(a_g, 0, len_w, b_w, sab_u.buf_w, c);
+
+      return u3i_slab_mint(&sab_u);
+    }
+  }
+}
+
+u3_noun
+u3wc_lsh(u3_noun cor)
+{
+  u3_atom bloq, step;
+  u3_noun a, b;
+  u3x_mean(cor, u3x_sam_2, &a,
+                u3x_sam_3, &b, 0);
+  u3x_bite(a, &bloq, &step);
+
+  return u3qc_lsh(bloq, step, u3x_atom(b));
+}
+
+u3_noun
+u3kc_lsh(u3_noun a,
+         u3_noun b,
+         u3_noun c)
+{
+  u3_noun d = u3qc_lsh(a, b, c);
+
+  u3z(a); u3z(b); u3z(c);
+  return d;
+}