kc3-lang/kc3

diff --git a/ic3/.ic3_history b/ic3/.ic3_history
index 07fec09..c3da4f5 100644
--- a/ic3/.ic3_history
+++ b/ic3/.ic3_history
@@ -1,4 +1,3 @@
-defmodule Plop do def a = 1 end
 Plop.a
 Plop
 defmodule Plop do def a = 1 end
@@ -97,3 +96,4 @@ a
 type(a)
 def operator_muul = %C3.Operator{sym: :****, symbol_value: cfn Tag "tag_mul" (Tag, Tag, Result), operator_precedence: 11, operator_associativity: :left}
 2 **** 4
+1 + 1
diff --git a/libc3/buf_parse.c b/libc3/buf_parse.c
index 6052dbd..dd82df2 100644
--- a/libc3/buf_parse.c
+++ b/libc3/buf_parse.c
@@ -27,6 +27,7 @@
 #include "complex.h"
 #include "cow.h"
 #include "env.h"
+#include "fact.h"
 #include "fn.h"
 #include "fn_clause.h"
 #include "ident.h"
@@ -1019,7 +1020,7 @@ sw buf_parse_cfn (s_buf *buf, s_cfn *dest)
   sw result = 0;
   const s_sym *result_type;
   s_buf_save save;
-  s_cfn tmp;
+  s_cfn tmp = {0};
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
@@ -1048,8 +1049,11 @@ sw buf_parse_cfn (s_buf *buf, s_cfn *dest)
     goto restore;
   result += r;
   cfn_init(&tmp, name_sym, arg_types, result_type);
+  // FIXME: implement env_eval_cfn
+  /*
   cfn_prep_cif(&tmp);
   cfn_link(&tmp);
+  */
   *dest = tmp;
   r = result;
   goto clean;
@@ -1481,12 +1485,10 @@ sw buf_parse_f64 (s_buf *buf, f64 *dest) {
 
 sw buf_parse_fact (s_buf *buf, s_fact_w *dest)
 {
-  s_tag *object = NULL;
-  s_tag *predicate = NULL;
   sw r;
   sw result = 0;
   s_buf_save save;
-  s_tag *subject = NULL;
+  s_fact_w tmp = {0};
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
@@ -1499,7 +1501,7 @@ sw buf_parse_fact (s_buf *buf, s_fact_w *dest)
   if ((r = buf_ignore_spaces(buf)) < 0)
     goto restore;
   result += r;
-  if ((r = buf_parse_new_tag(buf, &subject)) <= 0)
+  if ((r = buf_parse_tag(buf, &tmp.subject)) <= 0)
     goto restore;
   result += r;
   if ((r = buf_parse_comments(buf)) < 0)
@@ -1517,7 +1519,7 @@ sw buf_parse_fact (s_buf *buf, s_fact_w *dest)
   if ((r = buf_ignore_spaces(buf)) < 0)
     goto restore;
   result += r;
-  if ((r = buf_parse_new_tag(buf, &predicate)) <= 0)
+  if ((r = buf_parse_tag(buf, &tmp.predicate)) <= 0)
     goto restore;
   result += r;
   if ((r = buf_parse_comments(buf)) < 0)
@@ -1535,7 +1537,7 @@ sw buf_parse_fact (s_buf *buf, s_fact_w *dest)
   if ((r = buf_ignore_spaces(buf)) < 0)
     goto restore;
   result += r;
-  if ((r = buf_parse_new_tag(buf, &object)) <= 0)
+  if ((r = buf_parse_tag(buf, &tmp.object)) <= 0)
     goto restore;
   result += r;
   if ((r = buf_parse_comments(buf)) < 0)
@@ -1547,19 +1549,12 @@ sw buf_parse_fact (s_buf *buf, s_fact_w *dest)
   if ((r = buf_read_1(buf, "}")) < 0)
     goto restore;
   result += r;
-  dest->subject = subject;
-  dest->predicate = predicate;
-  dest->object = object;
+  *dest = tmp;
   r = result;
   goto clean;
  restore:
+  fact_w_clean(&tmp);
   buf_save_restore_rpos(buf, &save);
-  if (subject)
-    tag_delete(subject);
-  if (predicate)
-    tag_delete(predicate);
-  if (object)
-    tag_delete(object);
  clean:
   buf_save_clean(buf, &save);
   return r;
diff --git a/libc3/cfn.c b/libc3/cfn.c
index cd5a8bd..0a7608b 100644
--- a/libc3/cfn.c
+++ b/libc3/cfn.c
@@ -215,7 +215,7 @@ s_cfn * cfn_init_copy (s_cfn *cfn, const s_cfn *src)
     return NULL;
   tmp.arity = src->arity;
   tmp.cif = src->cif;
-  if (src->arity) {
+  if (src->arity && src->cif.arg_types) {
     tmp.cif.arg_types = alloc((src->cif.nargs + 1) * sizeof(ffi_type *));
     if (! tmp.cif.arg_types) {
       list_delete_all(tmp.arg_types);
diff --git a/libc3/env.c b/libc3/env.c
index 9ecfb28..94ad8eb 100644
--- a/libc3/env.c
+++ b/libc3/env.c
@@ -578,6 +578,23 @@ bool env_eval_call_resolve (s_env *env, s_call *call)
   return true;
 }
 
+bool env_eval_cfn (s_env *env, const s_cfn *cfn, s_tag *dest)
+{
+  s_cfn tmp;
+  assert(cfn);
+  assert(dest);
+  (void) env;
+  if (! cfn_init_copy(&tmp, cfn))
+    return false;
+  if (! cfn_prep_cif(&tmp))
+    return false;
+  if (! cfn_link(&tmp))
+    return false;
+  dest->type = TAG_CFN;
+  dest->data.cfn = tmp;
+  return true;
+}
+
 bool env_eval_complex (s_env *env, const s_complex *c, s_tag *dest)
 {
   s_complex *tmp = NULL;
@@ -1512,6 +1529,8 @@ bool env_eval_tag (s_env *env, const s_tag *tag, s_tag *dest)
     return env_eval_block(env, &tag->data.block, dest);
   case TAG_CALL:
     return env_eval_call(env, &tag->data.call, dest);
+  case TAG_CFN:
+    return env_eval_cfn(env, &tag->data.cfn, dest);
   case TAG_COMPLEX:
     return env_eval_complex(env, tag->data.complex, dest);
   case TAG_COW:
@@ -1533,7 +1552,6 @@ bool env_eval_tag (s_env *env, const s_tag *tag, s_tag *dest)
   case TAG_TUPLE:
     return env_eval_tuple(env, &tag->data.tuple, dest);
   case TAG_BOOL:
-  case TAG_CFN:
   case TAG_CHARACTER:
   case TAG_F32:
   case TAG_F64:
@@ -1595,6 +1613,41 @@ bool env_eval_void (s_env *env, const void *_, s_tag *dest)
   return true;
 }
 
+s_fact_w * env_fact_w_eval (s_env *env, const s_fact_w *fact,
+			    s_fact_w *dest)
+{
+  s_fact_w tmp = {0};
+  assert(env);
+  assert(fact);
+  assert(dest);
+  if (fact->subject.type == TAG_CFN) {
+    if (! env_eval_tag(env, &fact->subject, &tmp.subject))
+      return NULL;
+  }
+  else {
+    if (! tag_init_copy(&tmp.subject, &fact->subject))
+      return NULL;
+  }
+  if (fact->predicate.type == TAG_CFN) {
+    if (! env_eval_tag(env, &fact->predicate, &tmp.predicate))
+      return NULL;
+  }
+  else {
+    if (! tag_init_copy(&tmp.predicate, &fact->predicate))
+      return NULL;
+  }
+  if (fact->object.type == TAG_CFN) {
+    if (! env_eval_tag(env, &fact->object, &tmp.object))
+      return NULL;
+  }
+  else {
+    if (! tag_init_copy(&tmp.object, &fact->object))
+      return NULL;
+  }
+  *dest = tmp;
+  return dest;
+}
+
 const s_tag * env_frames_get (const s_env *env, const s_sym *name)
 {
   const s_tag *tag;
@@ -1944,7 +1997,6 @@ bool env_module_maybe_reload (s_env *env, const s_sym *module,
   }
   if (! r)
     return false;
-  //io_inspect_str(&path);
   if (! file_mtime(&path, &tag_mtime)) {
     str_clean(&path);
     return false;
@@ -2292,8 +2344,8 @@ bool * env_struct_type_exists (s_env *env, const s_sym *module,
     return NULL;
   if (! facts_cursor_next(&cursor, &fact))
     return NULL;
-  facts_cursor_clean(&cursor);
   *dest = fact ? true : false;
+  facts_cursor_clean(&cursor);
   return dest;
 }
 
diff --git a/libc3/env.h b/libc3/env.h
index 26abfca..7730ac9 100644
--- a/libc3/env.h
+++ b/libc3/env.h
@@ -66,6 +66,7 @@ bool          env_eval_call_fn_args (s_env *env, const s_fn *fn,
                                      const s_list *arguments,
                                      s_tag *dest);
 bool          env_eval_call_resolve (s_env *env, s_call *call);
+bool          env_eval_cfn (s_env *env, const s_cfn *cfn, s_tag *dest);
 bool          env_eval_complex (s_env *env, const s_complex *c,
                                 s_tag *dest);
 bool          env_eval_cow (s_env *env, const s_cow *cow, s_tag *dest);
@@ -161,6 +162,8 @@ bool          env_eval_tag (s_env *env, const s_tag *tag,
 bool          env_eval_tuple (s_env *env, const s_tuple *tuple,
                               s_tag *dest);
 bool          env_eval_void (s_env *env, const void *_, s_tag *dest);
+s_fact_w *    env_fact_w_eval (s_env *env, const s_fact_w *fact,
+			       s_fact_w *dest);
 bool *        env_ident_is_special_operator (s_env *env,
                                              const s_ident *ident,
                                              bool *dest);
diff --git a/libc3/fact.c b/libc3/fact.c
index 11cd450..2737b9f 100644
--- a/libc3/fact.c
+++ b/libc3/fact.c
@@ -91,17 +91,24 @@ s_str * fact_inspect (const s_fact *fact, s_str *dest)
   return buf_to_str(&buf, dest);
 }
 
-s_fact * fact_r (const s_fact_w *fact)
+void fact_r (const s_fact_w *fact, s_fact *dest)
 {
-  return (s_fact *) fact;
+  s_fact tmp = {0};
+  tmp.subject = &fact->subject;
+  tmp.predicate = &fact->predicate;
+  tmp.object = &fact->object;
+  tmp.id = fact->id;
+  *dest = tmp;
 }
 
 void fact_w_clean (s_fact_w *fact)
 {
-  tag_delete(fact->subject);
-  fact->subject = NULL;
-  tag_delete(fact->predicate);
-  fact->predicate = NULL;
-  tag_delete(fact->object);
-  fact->object = NULL;
+  tag_clean(&fact->subject);
+  tag_clean(&fact->predicate);
+  tag_clean(&fact->object);
+}
+
+s_fact_w * fact_w_eval (const s_fact_w *fact, s_fact_w *dest)
+{
+  return env_fact_w_eval(&g_c3_env, fact, dest);
 }
diff --git a/libc3/fact.h b/libc3/fact.h
index 9c1d43c..16563f4 100644
--- a/libc3/fact.h
+++ b/libc3/fact.h
@@ -22,13 +22,14 @@ s_fact * fact_init (s_fact *fact, const s_tag *subject,
 s_fact * fact_init_cast (s_fact *fact, const s_sym * const *type,
                          const s_tag *tag);
 s_fact * fact_init_copy (s_fact *fact, const s_fact *src);
+void     fact_w_clean (s_fact_w *fact);
 
 /* Observers */
 uw *     fact_hash_uw (const s_fact *fact, uw *dest);
 s_str *  fact_inspect (const s_fact *fact, s_str *dest);
-s_fact * fact_r (const s_fact_w *fact);
+void     fact_r (const s_fact_w *fact, s_fact *dest);
 
-/* Modifiers */
-void fact_w_clean (s_fact_w *fact);
+/* Operators */
+s_fact_w * fact_w_eval (const s_fact_w *fact, s_fact_w *dest);
 
 #endif /* LIBC3_FACT_H */
diff --git a/libc3/facts.c b/libc3/facts.c
index 313e92e..a0962ec 100644
--- a/libc3/facts.c
+++ b/libc3/facts.c
@@ -307,7 +307,8 @@ s_facts * facts_init (s_facts *facts)
 sw facts_load (s_facts *facts, s_buf *buf, const s_str *path)
 {
   s_fact_w fact;
-  s_fact *factp;
+  s_fact_w fact_eval;
+  s_fact   fact_eval_r;
   u64 line;
   sw r;
   bool replace;
@@ -316,8 +317,11 @@ sw facts_load (s_facts *facts, s_buf *buf, const s_str *path)
   assert(buf);
   if ((r = buf_read_1(buf,
                       "%{module: C3.Facts.Dump,\n"
-                      "  version: 1}\n")) <= 0)
-    goto ko_header;
+                      "  version: 1}\n")) <= 0) {
+    err_write_1("facts_load: invalid or missing header: ");
+    err_puts(path->ptr.pchar);
+    return -1;
+  }
   result += r;
   facts_lock_w(facts);
   line = 3;
@@ -332,36 +336,62 @@ sw facts_load (s_facts *facts, s_buf *buf, const s_str *path)
         break;
     }
     result += r;
-    if ((r = buf_parse_fact(buf, &fact)) <= 0)
-      goto ko_fact;
+    if ((r = buf_parse_fact(buf, &fact)) <= 0) {
+      err_write_1("facts_load: invalid fact line ");
+      err_inspect_u64(&line);
+      err_write_1(": ");
+      err_puts(path->ptr.pchar);
+      goto ko;
+    }
     result += r;
-    factp = fact_r(&fact);
-    if (replace)
-      facts_replace_fact(facts, factp);
-    else
-      facts_add_fact(facts, factp);
-    fact_w_clean(&fact);
     if ((r = buf_read_1(buf, "\n")) <= 0) {
-      r = -1;
-      goto ko_fact;
+      fact_w_clean(&fact);
+      err_write_1("facts_load: missing newline line ");
+      err_inspect_u64(&line);
+      err_write_1(": ");
+      err_puts(path->ptr.pchar);
+      goto ko;
     }
     result += r;
+    if (! fact_w_eval(&fact, &fact_eval)) {
+      fact_w_clean(&fact);
+      err_write_1("facts_load: invalid fact line ");
+      err_inspect_u64(&line);
+      err_write_1(": ");
+      err_puts(path->ptr.pchar);
+      goto ko;
+    }
+    fact_r(&fact_eval, &fact_eval_r);
+    if (replace) {
+      if (! facts_replace_fact(facts, &fact_eval_r)) {
+	fact_w_clean(&fact_eval);
+	fact_w_clean(&fact);
+	err_write_1("facts_load: failed to replace fact line ");
+	err_inspect_u64(&line);
+	err_write_1(": ");
+	err_puts(path->ptr.pchar);
+	goto ko;
+      }
+    }
+    else {
+      if (! facts_add_fact(facts, &fact_eval_r)) {
+	fact_w_clean(&fact_eval);
+	fact_w_clean(&fact);
+	err_write_1("facts_load: failed to add fact line ");
+	err_inspect_u64(&line);
+	err_write_1(": ");
+	err_puts(path->ptr.pchar);
+	goto ko;
+      }
+    }
+    fact_w_clean(&fact);
+    fact_w_clean(&fact_eval);
     line++;
   }
   facts_lock_unlock_w(facts);
   return result;
- ko_header:
-  err_write_1("facts_load: invalid or missing header: ");
-  err_puts(path->ptr.pchar);
-  return -1;
- ko_fact:
+ ko:
   facts_lock_unlock_w(facts);
-  err_write_1("facts_load: ");
-  err_write_1(r ? "invalid" : "missing");
-  err_write_1(" fact line ");
-  err_inspect_u64(&line);
-  err_write_1(": ");
-  err_puts(path->ptr.pchar);
   return -1;
 }
 
@@ -591,8 +621,8 @@ sw facts_open_file_create (s_facts *facts, const s_str *path)
 sw facts_open_log (s_facts *facts, s_buf *buf)
 {
   bool b;
-  s_fact_w fact;
-  s_fact *factp;
+  s_fact_w fact_w;
+  s_fact fact;
   sw r;
   sw result = 0;
   assert(facts);
@@ -602,25 +632,25 @@ sw facts_open_log (s_facts *facts, s_buf *buf)
       break;
     result += r;
     if (r) {
-      if ((r = buf_parse_fact(buf, &fact)) <= 0)
+      if ((r = buf_parse_fact(buf, &fact_w)) <= 0)
         break;
       result += r;
-      factp = fact_r(&fact);
-      if (! facts_add_fact(facts, factp))
+      fact_r(&fact_w, &fact);
+      if (! facts_add_fact(facts, &fact))
         return -1;
       goto ok;
     }
     if ((r = buf_read_1(buf, "remove ")) <= 0)
       break;
     result += r;
-    if ((r = buf_parse_fact(buf, &fact)) <= 0)
+    if ((r = buf_parse_fact(buf, &fact_w)) <= 0)
       break;
     result += r;
-    factp = fact_r(&fact);
-    if (! facts_remove_fact(facts, factp, &b))
+    fact_r(&fact_w, &fact);
+    if (! facts_remove_fact(facts, &fact, &b))
       return -1;
   ok:
-    fact_w_clean(&fact);
+    fact_w_clean(&fact_w);
     if ((r = buf_read_1(buf, "\n")) <= 0)
       break;
     result += r;
diff --git a/libc3/module.c b/libc3/module.c
index 6d66c60..b047774 100644
--- a/libc3/module.c
+++ b/libc3/module.c
@@ -161,12 +161,6 @@ s_str * module_path (const s_sym *module, const s_str *prefix,
   if ((r = buf_write_1(&out, ext)) < 0)
     goto error;
   result = buf_to_str(&out, dest);
-  /*
-  if (result) {
-    err_inspect_str(dest);
-    err_write_1("\n");
-  }
-  */
   return result;
  error:
   buf_clean(&out);
diff --git a/libc3/types.h b/libc3/types.h
index 7ab9cfa..86f7579 100644
--- a/libc3/types.h
+++ b/libc3/types.h
@@ -238,13 +238,6 @@ struct fact {
   uw id; /* serial id */
 };
 
-struct fact_w {
-  s_tag *subject;
-  s_tag *predicate;
-  s_tag *object;
-  uw id; /* serial id */
-};
-
 struct facts_transaction {
   s_fact_action *log;
   s_facts_transaction *next;
@@ -531,6 +524,13 @@ struct error_handler
   s_tag tag;
 };
 
+struct fact_w {
+  s_tag subject;
+  s_tag predicate;
+  s_tag object;
+  uw id; /* serial id */
+};
+
 struct list {
   s_tag tag;
   s_tag next;