1 files changed, 87 insertions, 0 deletions
diff --git a/vere/pkg/noun/jets/c/hew.c b/vere/pkg/noun/jets/c/hew.c
new file mode 100644
index 0000000..be6b7a7
--- /dev/null
+++ b/vere/pkg/noun/jets/c/hew.c
@@ -0,0 +1,87 @@
+/// @file
+
+#include "jets/q.h"
+#include "jets/w.h"
+
+#include "noun.h"
+
+static c3_w
+_hew_in(c3_g     a_g,
+        c3_w   pos_w,
+        u3_atom  vat,
+        u3_noun  sam,
+        u3_noun* out)
+{
+  u3_noun h, t, *l, *r;
+
+  while ( c3y == u3r_cell(sam, &h, &t) ) {
+    *out  = u3i_defcons(&l, &r);
+    pos_w = _hew_in(a_g, pos_w, vat, h, l);
+    sam   = t;
+    out   = r;
+  }
+
+  if ( !_(u3a_is_cat(sam)) ) {
+    return u3m_bail(c3__fail);
+  }
+
+  if ( !sam ) {
+    *out = 0;
+    return pos_w;
+  }
+  else {
+    c3_w     wid_w = (c3_w)sam;
+    c3_w     new_w = pos_w + wid_w;
+    u3i_slab sab_u;
+
+    if ( new_w < pos_w ) {
+      return u3m_bail(c3__fail);
+    }
+
+    u3i_slab_init(&sab_u, a_g, wid_w);
+    u3r_chop(a_g, pos_w, wid_w, 0, sab_u.buf_w, vat);
+
+    *out = u3i_slab_mint(&sab_u);
+    return new_w;
+  }
+}
+
+u3_noun
+u3qc_hew(u3_atom boq,
+         u3_atom sep,
+         u3_atom vat,
+         u3_noun sam)
+{
+  if ( !_(u3a_is_cat(boq)) || (boq >= 32) ) {
+    return u3m_bail(c3__fail);
+  }
+
+  if ( !_(u3a_is_cat(sep)) ) {
+    return u3m_bail(c3__fail);
+  }
+
+  u3_noun pro;
+  c3_w  pos_w = _hew_in((c3_g)boq, (c3_w)sep, vat, sam, &pro);
+  return u3nt(pro, boq, u3i_word(pos_w));
+}
+
+u3_noun
+u3wc_hew(u3_noun cor)
+{
+  u3_atom boq, sep, vat;
+  u3_noun sam;
+  {
+    u3_noun pay = u3t(cor);
+    u3_noun con = u3t(pay);
+    u3_noun gat = u3t(con);       // outer gate
+    u3_noun cam = u3h(u3t(gat));  // outer sample
+    u3_noun   d = u3h(con);
+
+    boq = u3x_atom(u3h(d));
+    sep = u3x_atom(u3t(d));
+    vat = u3x_atom(u3t(cam));
+    sam = u3h(pay);
+  }
+
+  return u3qc_hew(boq, sep, vat, sam);
+}