From 5254e80932adadfc024fc24178e6b13a268ea467 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Sat, 20 Feb 2016 00:03:16 +0900
Subject: [PATCH] struct pic_proc * -> pic_value

---
 contrib/10.callcc/callcc.c          | 13 +++---
 contrib/40.srfi/src/106.c           |  5 +--
 extlib/benz/cont.c                  | 40 +++++++-----------
 extlib/benz/debug.c                 |  6 +--
 extlib/benz/dict.c                  |  6 +--
 extlib/benz/error.c                 | 23 ++++------
 extlib/benz/eval.c                  |  4 +-
 extlib/benz/include/picrin.h        | 25 ++++++-----
 extlib/benz/include/picrin/cont.h   |  2 +-
 extlib/benz/include/picrin/object.h |  6 +--
 extlib/benz/macro.c                 | 22 +++++-----
 extlib/benz/pair.c                  | 16 +++----
 extlib/benz/port.c                  |  2 +-
 extlib/benz/proc.c                  | 65 +++++++++++++----------------
 extlib/benz/string.c                | 10 ++---
 extlib/benz/var.c                   | 35 +++++++---------
 extlib/benz/vector.c                | 10 ++---
 extlib/benz/weak.c                  |  9 +---
 18 files changed, 128 insertions(+), 171 deletions(-)

diff --git a/contrib/10.callcc/callcc.c b/contrib/10.callcc/callcc.c
index b3d9a96c..bacfee60 100644
--- a/contrib/10.callcc/callcc.c
+++ b/contrib/10.callcc/callcc.c
@@ -239,7 +239,7 @@ cont_call(pic_state *pic)
 }
 
 static pic_value
-pic_callcc(pic_state *pic, struct pic_proc *proc)
+pic_callcc(pic_state *pic, pic_value proc)
 {
   struct pic_fullcont *cont;
 
@@ -248,13 +248,12 @@ pic_callcc(pic_state *pic, struct pic_proc *proc)
     return pic_valuesk(pic, cont->retc, cont->retv);
   }
   else {
-    struct pic_proc *c;
-    pic_value args[1];
+    pic_value c, args[1];
 
     /* save the continuation object in proc */
     c = pic_lambda(pic, cont_call, 1, pic_data_value(pic, cont, &cont_type));
 
-    args[0] = pic_obj_value(c);
+    args[0] = c;
     return pic_applyk(pic, proc, 1, args);
   }
 }
@@ -262,15 +261,15 @@ pic_callcc(pic_state *pic, struct pic_proc *proc)
 static pic_value
 pic_callcc_callcc(pic_state *pic)
 {
-  struct pic_proc *proc;
+  pic_value proc;
 
   pic_get_args(pic, "l", &proc);
 
   return pic_callcc(pic, proc);
 }
 
-#define pic_redefun(pic, lib, name, func)                               \
-  pic_set(pic, lib, name, pic_obj_value(pic_lambda(pic, func, 0)))
+#define pic_redefun(pic, lib, name, func)               \
+  pic_set(pic, lib, name, pic_lambda(pic, func, 0))
 
 void
 pic_init_callcc(pic_state *pic)
diff --git a/contrib/40.srfi/src/106.c b/contrib/40.srfi/src/106.c
index b82c0f6f..f673c088 100644
--- a/contrib/40.srfi/src/106.c
+++ b/contrib/40.srfi/src/106.c
@@ -367,8 +367,7 @@ pic_socket_socket_output_port(pic_state *pic)
 static pic_value
 pic_socket_call_with_socket(pic_state *pic)
 {
-  pic_value obj, result;
-  struct pic_proc *proc;
+  pic_value obj, proc, result;
   struct pic_socket_t *sock;
 
   pic_get_args(pic, "ol", &obj, &proc);
@@ -389,7 +388,7 @@ pic_init_srfi_106(pic_state *pic)
 {
   pic_deflibrary(pic, "srfi.106");
 
-#define pic_defun_(pic, name, f) pic_define(pic, "srfi.106", name, pic_obj_value(pic_lambda(pic, f, 0)))
+#define pic_defun_(pic, name, f) pic_define(pic, "srfi.106", name, pic_lambda(pic, f, 0))
 #define pic_define_(pic, name, v) pic_define(pic, "srfi.106", name, v)
 
   pic_defun_(pic, "socket?", pic_socket_socket_p);
diff --git a/extlib/benz/cont.c b/extlib/benz/cont.c
index 4007b558..755b02e7 100644
--- a/extlib/benz/cont.c
+++ b/extlib/benz/cont.c
@@ -48,38 +48,34 @@ pic_wind(pic_state *pic, pic_checkpoint *here, pic_checkpoint *there)
 
   if (here->depth < there->depth) {
     pic_wind(pic, here, there->prev);
-    pic_call(pic, there->in, 0);
+    pic_call(pic, pic_obj_value(there->in), 0);
   }
   else {
-    pic_call(pic, there->out, 0);
+    pic_call(pic, pic_obj_value(there->out), 0);
     pic_wind(pic, here->prev, there);
   }
 }
 
 static pic_value
-pic_dynamic_wind(pic_state *pic, struct pic_proc *in, struct pic_proc *thunk, struct pic_proc *out)
+pic_dynamic_wind(pic_state *pic, pic_value in, pic_value thunk, pic_value out)
 {
   pic_checkpoint *here;
   pic_value val;
 
-  if (in != NULL) {
-    pic_call(pic, in, 0);       /* enter */
-  }
+  pic_call(pic, in, 0);       /* enter */
 
   here = pic->cp;
   pic->cp = (pic_checkpoint *)pic_obj_alloc(pic, sizeof(pic_checkpoint), PIC_TYPE_CP);
   pic->cp->prev = here;
   pic->cp->depth = here->depth + 1;
-  pic->cp->in = in;
-  pic->cp->out = out;
+  pic->cp->in = pic_proc_ptr(pic, in);
+  pic->cp->out = pic_proc_ptr(pic, out);
 
   val = pic_call(pic, thunk, 0);
 
   pic->cp = here;
 
-  if (out != NULL) {
-    pic_call(pic, out, 0);      /* exit */
-  }
+  pic_call(pic, out, 0);      /* exit */
 
   return val;
 }
@@ -120,20 +116,17 @@ cont_call(pic_state *pic)
   PIC_UNREACHABLE();
 }
 
-struct pic_proc *
+pic_value
 pic_make_cont(pic_state *pic, struct pic_cont *cont)
 {
   static const pic_data_type cont_type = { "cont", NULL, NULL };
-  struct pic_proc *c;
 
   /* save the escape continuation in proc */
-  c = pic_lambda(pic, cont_call, 2, pic_int_value(pic, cont->id), pic_data_value(pic, cont, &cont_type));
-
-  return c;
+  return pic_lambda(pic, cont_call, 2, pic_int_value(pic, cont->id), pic_data_value(pic, cont, &cont_type));
 }
 
 static pic_value
-pic_callcc(pic_state *pic, struct pic_proc *proc)
+pic_callcc(pic_state *pic, pic_value proc)
 {
   struct pic_cont cont;
 
@@ -145,7 +138,7 @@ pic_callcc(pic_state *pic, struct pic_proc *proc)
   else {
     pic_value val;
 
-    val = pic_call(pic, proc, 1, pic_obj_value(pic_make_cont(pic, &cont)));
+    val = pic_call(pic, proc, 1, pic_make_cont(pic, &cont));
 
     pic->cc = pic->cc->prev;
 
@@ -209,17 +202,17 @@ pic_receive(pic_state *pic, int n, pic_value *argv)
 static pic_value
 pic_cont_callcc(pic_state *pic)
 {
-  struct pic_proc *cb;
+  pic_value f;
 
-  pic_get_args(pic, "l", &cb);
+  pic_get_args(pic, "l", &f);
 
-  return pic_callcc(pic, cb);
+  return pic_callcc(pic, f);
 }
 
 static pic_value
 pic_cont_dynamic_wind(pic_state *pic)
 {
-  struct pic_proc *in, *thunk, *out;
+  pic_value in, thunk, out;
 
   pic_get_args(pic, "lll", &in, &thunk, &out);
 
@@ -240,9 +233,8 @@ pic_cont_values(pic_state *pic)
 static pic_value
 pic_cont_call_with_values(pic_state *pic)
 {
-  struct pic_proc *producer, *consumer;
+  pic_value producer, consumer, *retv;
   int retc;
-  pic_value *retv;
 
   pic_get_args(pic, "ll", &producer, &consumer);
 
diff --git a/extlib/benz/debug.c b/extlib/benz/debug.c
index b8e5e215..c354c89f 100644
--- a/extlib/benz/debug.c
+++ b/extlib/benz/debug.c
@@ -15,14 +15,14 @@ pic_get_backtrace(pic_state *pic)
   trace = pic_lit_value(pic, "");
 
   for (ci = pic->ci; ci != pic->cibase; --ci) {
-    struct pic_proc *proc = pic_proc_ptr(ci->fp[0]);
+    pic_value proc = ci->fp[0];
 
     trace = pic_str_cat(pic, trace, pic_lit_value(pic, "  at "));
     trace = pic_str_cat(pic, trace, pic_lit_value(pic, "(anonymous lambda)"));
 
-    if (pic_proc_func_p(proc)) {
+    if (pic_proc_func_p(pic_proc_ptr(pic, proc))) {
       trace = pic_str_cat(pic, trace, pic_lit_value(pic, " (native function)\n"));
-    } else if (pic_proc_irep_p(proc)) {
+    } else {
       trace = pic_str_cat(pic, trace, pic_lit_value(pic, " (unknown location)\n")); /* TODO */
     }
   }
diff --git a/extlib/benz/dict.c b/extlib/benz/dict.c
index 88c67e4c..301d0c4b 100644
--- a/extlib/benz/dict.c
+++ b/extlib/benz/dict.c
@@ -168,8 +168,7 @@ pic_dict_dictionary_size(pic_state *pic)
 static pic_value
 pic_dict_dictionary_map(pic_state *pic)
 {
-  struct pic_proc *proc;
-  pic_value dict, ret = pic_nil_value(pic);
+  pic_value dict, proc, ret = pic_nil_value(pic);
   pic_sym *key;
   int it = 0;
 
@@ -184,8 +183,7 @@ pic_dict_dictionary_map(pic_state *pic)
 static pic_value
 pic_dict_dictionary_for_each(pic_state *pic)
 {
-  struct pic_proc *proc;
-  pic_value dict;
+  pic_value dict, proc;
   pic_sym *key;
   int it;
 
diff --git a/extlib/benz/error.c b/extlib/benz/error.c
index 2b203ed1..0686ff9e 100644
--- a/extlib/benz/error.c
+++ b/extlib/benz/error.c
@@ -51,21 +51,18 @@ pic_value
 pic_native_exception_handler(pic_state *pic)
 {
   pic_value err;
-  struct pic_proc *self, *cont;
 
-  pic_get_args(pic, "&o", &self, &err);
+  pic_get_args(pic, "o", &err);
 
   pic->err = err;
 
-  cont = pic_proc_ptr(pic_closure_ref(pic, 0));
-
-  pic_call(pic, cont, 1, pic_false_value(pic));
+  pic_call(pic, pic_closure_ref(pic, 0), 1, pic_false_value(pic));
 
   PIC_UNREACHABLE();
 }
 
 void
-pic_push_handler(pic_state *pic, struct pic_proc *handler)
+pic_push_handler(pic_state *pic, pic_value handler)
 {
   size_t xp_len;
   ptrdiff_t xp_offset;
@@ -78,17 +75,17 @@ pic_push_handler(pic_state *pic, struct pic_proc *handler)
     pic->xpend = pic->xpbase + xp_len;
   }
 
-  *pic->xp++ = handler;
+  *pic->xp++ = pic_proc_ptr(pic, handler);
 }
 
-struct pic_proc *
+pic_value
 pic_pop_handler(pic_state *pic)
 {
   if (pic->xp == pic->xpbase) {
     pic_panic(pic, "no exception handler registered");
   }
 
-  return *--pic->xp;
+  return pic_obj_value(*--pic->xp);
 }
 
 struct pic_error *
@@ -112,12 +109,11 @@ pic_make_error(pic_state *pic, const char *type, const char *msg, pic_value irrs
 pic_value
 pic_raise_continuable(pic_state *pic, pic_value err)
 {
-  struct pic_proc *handler;
-  pic_value v;
+  pic_value handler, v;
 
   handler = pic_pop_handler(pic);
 
-  pic_protect(pic, pic_obj_value(handler));
+  pic_protect(pic, handler);
 
   v = pic_call(pic, handler, 1, err);
 
@@ -151,8 +147,7 @@ pic_error(pic_state *pic, const char *type, const char *msg, pic_value irrs)
 static pic_value
 pic_error_with_exception_handler(pic_state *pic)
 {
-  struct pic_proc *handler, *thunk;
-  pic_value val;
+  pic_value handler, thunk, val;
 
   pic_get_args(pic, "ll", &handler, &thunk);
 
diff --git a/extlib/benz/eval.c b/extlib/benz/eval.c
index 64160c7f..eaf6a72a 100644
--- a/extlib/benz/eval.c
+++ b/extlib/benz/eval.c
@@ -831,11 +831,11 @@ pic_codegen(pic_state *pic, pic_value obj)
 
 #define SAVE(pic, ai, obj) pic_leave(pic, ai); pic_protect(pic, obj)
 
-struct pic_proc *
+pic_value
 pic_compile(pic_state *pic, pic_value obj)
 {
   struct pic_irep *irep;
-  struct pic_proc *proc;
+  pic_value proc;
   size_t ai = pic_enter(pic);
 
 #if DEBUG
diff --git a/extlib/benz/include/picrin.h b/extlib/benz/include/picrin.h
index 45130110..d86e461c 100644
--- a/extlib/benz/include/picrin.h
+++ b/extlib/benz/include/picrin.h
@@ -54,7 +54,6 @@ typedef struct {
 struct pic_object;
 struct pic_symbol;
 struct pic_string;
-struct pic_proc;
 struct pic_port;
 struct pic_error;
 struct pic_env;
@@ -85,7 +84,7 @@ void pic_gc(pic_state *);
 void pic_add_feature(pic_state *, const char *feature);
 
 void pic_defun(pic_state *, const char *name, pic_func_t f);
-void pic_defvar(pic_state *, const char *name, pic_value v, struct pic_proc *conv);
+void pic_defvar(pic_state *, const char *name, pic_value v, pic_value conv);
 
 void pic_define(pic_state *, const char *lib, const char *name, pic_value v);
 pic_value pic_ref(pic_state *, const char *lib, const char *name);
@@ -111,12 +110,12 @@ PIC_NORETURN void pic_errorf(pic_state *, const char *fmt, ...);
 PIC_NORETURN void pic_error(pic_state *, const char *type, const char *msg, pic_value irrs);
 PIC_NORETURN void pic_raise(pic_state *, pic_value v);
 
-struct pic_proc *pic_lambda(pic_state *, pic_func_t f, int n, ...);
-struct pic_proc *pic_vlambda(pic_state *, pic_func_t f, int n, va_list);
-pic_value pic_call(pic_state *, struct pic_proc *proc, int, ...);
-pic_value pic_vcall(pic_state *, struct pic_proc *proc, int, va_list);
-pic_value pic_apply(pic_state *, struct pic_proc *proc, int n, pic_value *argv);
-pic_value pic_applyk(pic_state *, struct pic_proc *proc, int n, pic_value *argv);
+pic_value pic_lambda(pic_state *, pic_func_t f, int n, ...);
+pic_value pic_vlambda(pic_state *, pic_func_t f, int n, va_list);
+pic_value pic_call(pic_state *, pic_value proc, int, ...);
+pic_value pic_vcall(pic_state *, pic_value proc, int, va_list);
+pic_value pic_apply(pic_state *, pic_value proc, int n, pic_value *argv);
+pic_value pic_applyk(pic_state *, pic_value proc, int n, pic_value *argv);
 
 PIC_INLINE int pic_int(pic_state *, pic_value i);
 PIC_INLINE double pic_float(pic_state *, pic_value f);
@@ -301,7 +300,7 @@ pic_value pic_eval(pic_state *, pic_value, const char *);
 void pic_load(pic_state *, struct pic_port *);
 void pic_load_cstr(pic_state *, const char *);
 
-struct pic_proc *pic_make_var(pic_state *, pic_value, struct pic_proc *);
+pic_value pic_make_var(pic_state *, pic_value init, pic_value conv);
 
 bool pic_data_type_p(pic_state *, pic_value, const pic_data_type *);
 
@@ -320,14 +319,14 @@ bool pic_data_type_p(pic_state *, pic_value, const pic_data_type *);
   pic_catch_(PIC_GENSYM(label))
 #define pic_try_(cont, handler)                                         \
   do {                                                                  \
-    extern void pic_push_handler(pic_state *, struct pic_proc *);       \
-    extern struct pic_proc *pic_pop_handler(pic_state *);               \
+    extern void pic_push_handler(pic_state *, pic_value proc);          \
+    extern pic_value pic_pop_handler(pic_state *);                      \
     extern pic_value pic_native_exception_handler(pic_state *);         \
     struct pic_cont cont;                                               \
     pic_save_point(pic, &cont);                                         \
     if (PIC_SETJMP(pic, cont.jmp) == 0) {                               \
-      struct pic_proc *handler;                                         \
-      handler = pic_lambda(pic, pic_native_exception_handler, 1, pic_obj_value(pic_make_cont(pic, &cont))); \
+      pic_value handler;                                                \
+      handler = pic_lambda(pic, pic_native_exception_handler, 1, pic_make_cont(pic, &cont)); \
       do {                                                              \
         pic_push_handler(pic, handler);
 #define pic_catch_(label)                                 \
diff --git a/extlib/benz/include/picrin/cont.h b/extlib/benz/include/picrin/cont.h
index 4e6649bf..46742b0c 100644
--- a/extlib/benz/include/picrin/cont.h
+++ b/extlib/benz/include/picrin/cont.h
@@ -31,7 +31,7 @@ struct pic_cont {
 void pic_save_point(pic_state *, struct pic_cont *);
 void pic_load_point(pic_state *, struct pic_cont *);
 
-struct pic_proc *pic_make_cont(pic_state *, struct pic_cont *);
+pic_value pic_make_cont(pic_state *, struct pic_cont *);
 
 void pic_wind(pic_state *, pic_checkpoint *, pic_checkpoint *);
 
diff --git a/extlib/benz/include/picrin/object.h b/extlib/benz/include/picrin/object.h
index 1c1ad585..8970c77f 100644
--- a/extlib/benz/include/picrin/object.h
+++ b/extlib/benz/include/picrin/object.h
@@ -125,12 +125,12 @@ struct pic_port {
 #define pic_vec_ptr(pic, o) ((struct pic_vector *)pic_obj_ptr(o))
 #define pic_dict_ptr(pic, o) ((struct pic_dict *)pic_obj_ptr(o))
 #define pic_data_ptr(pic, o) ((struct pic_data *)pic_obj_ptr(o))
+#define pic_proc_ptr(pic, o) ((struct pic_proc *)pic_obj_ptr(o))
 #define pic_sym_ptr(v) ((pic_sym *)pic_obj_ptr(v))
 #define pic_id_ptr(v) ((pic_id *)pic_obj_ptr(v))
 #define pic_str_ptr(o) ((struct pic_string *)pic_obj_ptr(o))
 #define pic_weak_ptr(v) ((struct pic_weak *)pic_obj_ptr(v))
 #define pic_context_ptr(o) ((struct pic_context *)pic_obj_ptr(o))
-#define pic_proc_ptr(o) ((struct pic_proc *)pic_obj_ptr(o))
 #define pic_rec_ptr(v) ((struct pic_record *)pic_obj_ptr(v))
 #define pic_error_ptr(v) ((struct pic_error *)pic_obj_ptr(v))
 #define pic_port_ptr(v) ((struct pic_port *)pic_obj_ptr(v))
@@ -157,8 +157,8 @@ struct pic_object *pic_obj_alloc(pic_state *, size_t, int type);
   } while (0)
 
 pic_id *pic_make_identifier(pic_state *, pic_id *, struct pic_env *);
-struct pic_proc *pic_make_proc(pic_state *, pic_func_t, int, pic_value *);
-struct pic_proc *pic_make_proc_irep(pic_state *, struct pic_irep *, struct pic_context *);
+pic_value pic_make_proc(pic_state *, pic_func_t, int, pic_value *);
+pic_value pic_make_proc_irep(pic_state *, struct pic_irep *, struct pic_context *);
 struct pic_record *pic_make_rec(pic_state *, pic_value, pic_value);
 struct pic_error *pic_make_error(pic_state *, const char *, const char *, pic_value);
 struct pic_env *pic_make_env(pic_state *, struct pic_env *);
diff --git a/extlib/benz/macro.c b/extlib/benz/macro.c
index 34266ed1..9bb59afc 100644
--- a/extlib/benz/macro.c
+++ b/extlib/benz/macro.c
@@ -107,21 +107,21 @@ pic_find_identifier(pic_state *pic, pic_id *id, struct pic_env *env)
 
 
 static void
-define_macro(pic_state *pic, pic_sym *uid, struct pic_proc *mac)
+define_macro(pic_state *pic, pic_sym *uid, pic_value mac)
 {
   if (pic_weak_has(pic, pic->macros, uid)) {
     pic_warnf(pic, "redefining syntax variable: ~s", pic_obj_value(uid));
   }
-  pic_weak_set(pic, pic->macros, uid, pic_obj_value(mac));
+  pic_weak_set(pic, pic->macros, uid, mac);
 }
 
-static struct pic_proc *
+static pic_value
 find_macro(pic_state *pic, pic_sym *uid)
 {
   if (! pic_weak_has(pic, pic->macros, uid)) {
-    return NULL;
+    return pic_false_value(pic);
   }
-  return pic_proc_ptr(pic_weak_ref(pic, pic->macros, uid));
+  return pic_weak_ref(pic, pic->macros, uid);
 }
 
 static void
@@ -138,12 +138,12 @@ static pic_value expand_lambda(pic_state *, pic_value, struct pic_env *);
 static pic_value
 expand_var(pic_state *pic, pic_id *id, struct pic_env *env, pic_value deferred)
 {
-  struct pic_proc *mac;
+  pic_value mac;
   pic_sym *functor;
 
   functor = pic_find_identifier(pic, id, env);
 
-  if ((mac = find_macro(pic, functor)) != NULL) {
+  if (! pic_false_p(pic, mac = find_macro(pic, functor))) {
     return expand(pic, pic_call(pic, mac, 2, pic_obj_value(id), pic_obj_value(env)), env, deferred);
   }
   return pic_obj_value(functor);
@@ -250,7 +250,7 @@ expand_define(pic_state *pic, pic_value expr, struct pic_env *env, pic_value def
 static pic_value
 expand_defmacro(pic_state *pic, pic_value expr, struct pic_env *env)
 {
-  struct pic_proc *pic_compile(pic_state *, pic_value);
+  pic_value pic_compile(pic_state *, pic_value);
   pic_id *id;
   pic_value val;
   pic_sym *uid;
@@ -265,7 +265,7 @@ expand_defmacro(pic_state *pic, pic_value expr, struct pic_env *env)
     pic_errorf(pic, "macro definition \"%s\" evaluates to non-procedure object", pic_str(pic, pic_id_name(pic, id)));
   }
 
-  define_macro(pic, uid, pic_proc_ptr(val));
+  define_macro(pic, uid, val);
 
   return pic_undef_value(pic);
 }
@@ -279,7 +279,7 @@ expand_node(pic_state *pic, pic_value expr, struct pic_env *env, pic_value defer
     return expand_var(pic, pic_id_ptr(expr), env, deferred);
   }
   case PIC_TYPE_PAIR: {
-    struct pic_proc *mac;
+    pic_value mac;
 
     if (! pic_list_p(pic, expr)) {
       pic_errorf(pic, "cannot expand improper list: ~s", expr);
@@ -303,7 +303,7 @@ expand_node(pic_state *pic, pic_value expr, struct pic_env *env, pic_value defer
         return expand_quote(pic, expr);
       }
 
-      if ((mac = find_macro(pic, functor)) != NULL) {
+      if (! pic_false_p(pic, mac = find_macro(pic, functor))) {
         return expand(pic, pic_call(pic, mac, 2, expr, pic_obj_value(env)), env, deferred);
       }
     }
diff --git a/extlib/benz/pair.c b/extlib/benz/pair.c
index a58b6cc4..ff12994a 100644
--- a/extlib/benz/pair.c
+++ b/extlib/benz/pair.c
@@ -470,9 +470,8 @@ pic_pair_list_copy(pic_state *pic)
 static pic_value
 pic_pair_map(pic_state *pic)
 {
-  struct pic_proc *proc;
   int argc, i;
-  pic_value *args, *arg_list, ret;
+  pic_value proc, *args, *arg_list, ret;
 
   pic_get_args(pic, "l*", &proc, &argc, &args);
 
@@ -503,9 +502,8 @@ pic_pair_map(pic_state *pic)
 static pic_value
 pic_pair_for_each(pic_state *pic)
 {
-  struct pic_proc *proc;
   int argc, i;
-  pic_value *args, *arg_list;
+  pic_value proc, *args, *arg_list;
 
   pic_get_args(pic, "l*", &proc, &argc, &args);
 
@@ -563,13 +561,12 @@ pic_pair_memv(pic_state *pic)
 static pic_value
 pic_pair_member(pic_state *pic)
 {
-  struct pic_proc *proc = NULL;
-  pic_value key, list;
+  pic_value key, list, proc = pic_false_value(pic);
 
   pic_get_args(pic, "oo|l", &key, &list, &proc);
 
   while (! pic_nil_p(pic, list)) {
-    if (proc == NULL) {
+    if (pic_false_p(pic, proc)) {
       if (pic_equal_p(pic, key, pic_car(pic, list)))
         return list;
     } else {
@@ -618,14 +615,13 @@ pic_pair_assv(pic_state *pic)
 static pic_value
 pic_pair_assoc(pic_state *pic)
 {
-  struct pic_proc *proc = NULL;
-  pic_value key, alist, cell;
+  pic_value key, alist, proc = pic_false_value(pic), cell;
 
   pic_get_args(pic, "oo|l", &key, &alist, &proc);
 
   while (! pic_nil_p(pic, alist)) {
     cell = pic_car(pic, alist);
-    if (proc == NULL) {
+    if (pic_false_p(pic, proc)) {
       if (pic_equal_p(pic, key, pic_car(pic, cell)))
         return cell;
     } else {
diff --git a/extlib/benz/port.c b/extlib/benz/port.c
index 039dbf91..2e94e9f9 100644
--- a/extlib/benz/port.c
+++ b/extlib/benz/port.c
@@ -334,7 +334,7 @@ coerce_port(pic_state *pic)
 void
 pic_init_port(pic_state *pic)
 {
-  struct pic_proc *coerce = pic_lambda(pic, coerce_port, 0);
+  pic_value coerce = pic_lambda(pic, coerce_port, 0);
 
   DEFINE_PORT(pic, "current-input-port", xstdin);
   DEFINE_PORT(pic, "current-output-port", xstdout);
diff --git a/extlib/benz/proc.c b/extlib/benz/proc.c
index 017d691f..0aade676 100644
--- a/extlib/benz/proc.c
+++ b/extlib/benz/proc.c
@@ -24,7 +24,7 @@
  *  v   pic_value *             vector object
  *  s   struct pic_str **       string object
  *  b   pic_value *             bytevector object
- *  l   struct pic_proc **      lambda object
+ *  l   pic_value *             lambda object
  *  p   struct pic_port **      port object
  *  d   pic_value *             dictionary object
  *  e   struct pic_error **     error object
@@ -76,10 +76,10 @@ pic_get_args(pic_state *pic, const char *format, ...)
 
   /* dispatch */
   if (proc) {
-    struct pic_proc **proc;
+    pic_value *proc;
 
-    proc = va_arg(ap, struct pic_proc **);
-    *proc = pic_proc_ptr(GET_OPERAND(pic, 0));
+    proc = va_arg(ap, pic_value *);
+    *proc = GET_OPERAND(pic, 0);
   }
   for (i = 1; i <= MIN(paramc + optc, argc); ++i) {
 
@@ -149,13 +149,13 @@ pic_get_args(pic_state *pic, const char *format, ...)
 
     PTR_CASE('m', sym, pic_sym *)
     PTR_CASE('s', str, struct pic_string *)
-    PTR_CASE('l', proc, struct pic_proc *)
     PTR_CASE('p', port, struct pic_port *)
     PTR_CASE('e', error, struct pic_error *)
     PTR_CASE('r', rec, struct pic_record *)
 
 #define OBJ_CASE(c, type) VAL_CASE(c, type, pic_value, v)
 
+    OBJ_CASE('l', proc)
     OBJ_CASE('b', blob)
     OBJ_CASE('v', vec)
     OBJ_CASE('d', dict)
@@ -337,7 +337,7 @@ bool pic_gt(pic_state *, pic_value, pic_value);
 bool pic_ge(pic_state *, pic_value, pic_value);
 
 pic_value
-pic_apply(pic_state *pic, struct pic_proc *proc, int argc, pic_value *argv)
+pic_apply(pic_state *pic, pic_value proc, int argc, pic_value *argv)
 {
   pic_code c;
   size_t ai = pic_enter(pic);
@@ -363,7 +363,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, int argc, pic_value *argv)
   pic_callinfo *cibase;
 #endif
 
-  PUSH(pic_obj_value(proc));
+  PUSH(proc);
 
   for (i = 0; i < argc; ++i) {
     PUSH(argv[i]);
@@ -498,6 +498,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, int argc, pic_value *argv)
     CASE(OP_CALL) {
       pic_value x, v;
       pic_callinfo *ci;
+      struct pic_proc *proc;
 
       if (c.a == -1) {
         pic->sp += pic->ci[1].retc - 1;
@@ -509,7 +510,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, int argc, pic_value *argv)
       if (! pic_proc_p(pic, x)) {
 	pic_errorf(pic, "invalid application: ~s", x);
       }
-      proc = pic_proc_ptr(x);
+      proc = pic_proc_ptr(pic, x);
 
       VM_CALL_PRINT;
 
@@ -632,8 +633,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, int argc, pic_value *argv)
         vm_push_cxt(pic);
       }
 
-      proc = pic_make_proc_irep(pic, pic->ci->irep->irep[c.a], pic->ci->cxt);
-      PUSH(pic_obj_value(proc));
+      PUSH(pic_make_proc_irep(pic, pic->ci->irep->irep[c.a], pic->ci->cxt));
       pic_leave(pic, ai);
       NEXT;
     }
@@ -794,7 +794,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, int argc, pic_value *argv)
 }
 
 pic_value
-pic_applyk(pic_state *pic, struct pic_proc *proc, int argc, pic_value *args)
+pic_applyk(pic_state *pic, pic_value proc, int argc, pic_value *args)
 {
   pic_value *sp;
   pic_callinfo *ci;
@@ -803,7 +803,7 @@ pic_applyk(pic_state *pic, struct pic_proc *proc, int argc, pic_value *args)
   PIC_INIT_CODE_I(pic->iseq[0], OP_NOP, 0);
   PIC_INIT_CODE_I(pic->iseq[1], OP_TAILCALL, -1);
 
-  *pic->sp++ = pic_obj_value(proc);
+  *pic->sp++ = proc;
 
   sp = pic->sp;
   for (i = 0; i < argc; ++i) {
@@ -823,7 +823,7 @@ pic_applyk(pic_state *pic, struct pic_proc *proc, int argc, pic_value *args)
 }
 
 pic_value
-pic_call(pic_state *pic, struct pic_proc *proc, int n, ...)
+pic_call(pic_state *pic, pic_value proc, int n, ...)
 {
   pic_value r;
   va_list ap;
@@ -835,7 +835,7 @@ pic_call(pic_state *pic, struct pic_proc *proc, int n, ...)
 }
 
 pic_value
-pic_vcall(pic_state *pic, struct pic_proc *proc, int n, va_list ap)
+pic_vcall(pic_state *pic, pic_value proc, int n, va_list ap)
 {
   pic_value *args = pic_alloca(pic, sizeof(pic_value) * n);
   int i;
@@ -846,10 +846,10 @@ pic_vcall(pic_state *pic, struct pic_proc *proc, int n, va_list ap)
   return pic_apply(pic, proc, n, args);
 }
 
-struct pic_proc *
+pic_value
 pic_lambda(pic_state *pic, pic_func_t f, int n, ...)
 {
-  struct pic_proc *proc;
+  pic_value proc;
   va_list ap;
 
   va_start(ap, n);
@@ -858,7 +858,7 @@ pic_lambda(pic_state *pic, pic_func_t f, int n, ...)
   return proc;
 }
 
-struct pic_proc *
+pic_value
 pic_vlambda(pic_state *pic, pic_func_t f, int n, va_list ap)
 {
   pic_value *env = pic_alloca(pic, sizeof(pic_value) * n);
@@ -873,14 +873,14 @@ pic_vlambda(pic_state *pic, pic_func_t f, int n, va_list ap)
 void
 pic_defun(pic_state *pic, const char *name, pic_func_t f)
 {
-  pic_define(pic, pic_current_library(pic), name, pic_obj_value(pic_make_proc(pic, f, 0, NULL)));
+  pic_define(pic, pic_current_library(pic), name, pic_make_proc(pic, f, 0, NULL));
   pic_export(pic, pic_intern_cstr(pic, name));
 }
 
 void
-pic_defvar(pic_state *pic, const char *name, pic_value init, struct pic_proc *conv)
+pic_defvar(pic_state *pic, const char *name, pic_value init, pic_value conv)
 {
-  pic_define(pic, pic_current_library(pic), name, pic_obj_value(pic_make_var(pic, init, conv)));
+  pic_define(pic, pic_current_library(pic), name, pic_make_var(pic, init, conv));
   pic_export(pic, pic_intern_cstr(pic, name));
 }
 
@@ -939,31 +939,27 @@ pic_set(pic_state *pic, const char *lib, const char *name, pic_value val)
 pic_value
 pic_closure_ref(pic_state *pic, int n)
 {
-  struct pic_proc *self;
-
-  self = pic_proc_ptr(GET_OPERAND(pic, 0));
+  struct pic_proc *self = pic_proc_ptr(pic, GET_OPERAND(pic, 0));
 
   assert(pic_proc_func_p(self));
 
   if (n < 0 || self->u.f.localc <= n) {
     pic_errorf(pic, "pic_closure_ref: index out of range (%d)", n);
   }
-  return pic_proc_ptr(GET_OPERAND(pic, 0))->locals[n];
+  return self->locals[n];
 }
 
 void
 pic_closure_set(pic_state *pic, int n, pic_value v)
 {
-  struct pic_proc *self;
-
-  self = pic_proc_ptr(GET_OPERAND(pic, 0));
+  struct pic_proc *self = pic_proc_ptr(pic, GET_OPERAND(pic, 0));
 
   assert(pic_proc_func_p(self));
 
   if (n < 0 || self->u.f.localc <= n) {
     pic_errorf(pic, "pic_closure_ref: index out of range (%d)", n);
   }
-  pic_proc_ptr(GET_OPERAND(pic, 0))->locals[n] = v;
+  self->locals[n] = v;
 }
 
 pic_value
@@ -977,7 +973,7 @@ pic_funcall(pic_state *pic, const char *lib, const char *name, int n, ...)
   pic_assert_type(pic, proc, proc);
 
   va_start(ap, n);
-  r = pic_vcall(pic, pic_proc_ptr(proc), n, ap);
+  r = pic_vcall(pic, proc, n, ap);
   va_end(ap);
 
   return r;
@@ -1012,7 +1008,7 @@ pic_irep_decref(pic_state *pic, struct pic_irep *irep)
   }
 }
 
-struct pic_proc *
+pic_value
 pic_make_proc(pic_state *pic, pic_func_t func, int n, pic_value *env)
 {
   struct pic_proc *proc;
@@ -1025,10 +1021,10 @@ pic_make_proc(pic_state *pic, pic_func_t func, int n, pic_value *env)
   for (i = 0; i < n; ++i) {
     proc->locals[i] = env[i];
   }
-  return proc;
+  return pic_obj_value(proc);
 }
 
-struct pic_proc *
+pic_value
 pic_make_proc_irep(pic_state *pic, struct pic_irep *irep, struct pic_context *cxt)
 {
   struct pic_proc *proc;
@@ -1038,7 +1034,7 @@ pic_make_proc_irep(pic_state *pic, struct pic_irep *irep, struct pic_context *cx
   proc->u.i.irep = irep;
   proc->u.i.cxt = cxt;
   pic_irep_incref(pic, irep);
-  return proc;
+  return pic_obj_value(proc);
 }
 
 static pic_value
@@ -1054,8 +1050,7 @@ pic_proc_proc_p(pic_state *pic)
 static pic_value
 pic_proc_apply(pic_state *pic)
 {
-  struct pic_proc *proc;
-  pic_value *args, *arg_list;
+  pic_value proc, *args, *arg_list;
   int argc, n, i;
 
   pic_get_args(pic, "l*", &proc, &argc, &args);
diff --git a/extlib/benz/string.c b/extlib/benz/string.c
index d449953b..28d18426 100644
--- a/extlib/benz/string.c
+++ b/extlib/benz/string.c
@@ -552,8 +552,7 @@ pic_str_string_append(pic_state *pic)
 static pic_value
 pic_str_string_map(pic_state *pic)
 {
-  struct pic_proc *proc;
-  pic_value *argv, vals, val;
+  pic_value proc, *argv, vals, val;
   int argc, i, len, j;
   struct pic_string *str;
   char *buf;
@@ -581,7 +580,7 @@ pic_str_string_map(pic_state *pic)
       for (j = 0; j < argc; ++j) {
         pic_push(pic, pic_char_value(pic, pic_str_ref(pic, pic_str_ptr(argv[j]), i)), vals);
       }
-      val = pic_funcall(pic, "picrin.base", "apply", 2, pic_obj_value(proc), vals);
+      val = pic_funcall(pic, "picrin.base", "apply", 2, proc, vals);
 
       pic_assert_type(pic, val, char);
       buf[i] = pic_char(pic, val);
@@ -601,9 +600,8 @@ pic_str_string_map(pic_state *pic)
 static pic_value
 pic_str_string_for_each(pic_state *pic)
 {
-  struct pic_proc *proc;
   int argc, len, i, j;
-  pic_value *argv, vals;
+  pic_value proc, *argv, vals;
 
   pic_get_args(pic, "l*", &proc, &argc, &argv);
 
@@ -626,7 +624,7 @@ pic_str_string_for_each(pic_state *pic)
     for (j = 0; j < argc; ++j) {
       pic_push(pic, pic_char_value(pic, pic_str_ref(pic, pic_str_ptr(argv[j]), i)), vals);
     }
-    pic_funcall(pic, "picrin.base", "apply", 2, pic_obj_value(proc), vals);
+    pic_funcall(pic, "picrin.base", "apply", 2, proc, vals);
   }
 
   return pic_undef_value(pic);
diff --git a/extlib/benz/var.c b/extlib/benz/var.c
index 5b132a06..04a07e5e 100644
--- a/extlib/benz/var.c
+++ b/extlib/benz/var.c
@@ -6,28 +6,28 @@
 #include "picrin/object.h"
 
 static pic_value
-var_get(pic_state *pic, struct pic_proc *var)
+var_get(pic_state *pic, pic_value var)
 {
   pic_value elem, it;
   struct pic_weak *weak;
 
   pic_for_each (elem, pic->ptable, it) {
     weak = pic_weak_ptr(elem);
-    if (pic_weak_has(pic, weak, var)) {
-      return pic_weak_ref(pic, weak, var);
+    if (pic_weak_has(pic, weak, pic_obj_ptr(var))) {
+      return pic_weak_ref(pic, weak, pic_obj_ptr(var));
     }
   }
   pic_panic(pic, "logic flaw");
 }
 
 static pic_value
-var_set(pic_state *pic, struct pic_proc *var, pic_value val)
+var_set(pic_state *pic, pic_value var, pic_value val)
 {
   struct pic_weak *weak;
 
   weak = pic_weak_ptr(pic_car(pic, pic->ptable));
 
-  pic_weak_set(pic, weak, var, val);
+  pic_weak_set(pic, weak, pic_obj_ptr(var), val);
 
   return pic_undef_value(pic);
 }
@@ -35,8 +35,7 @@ var_set(pic_state *pic, struct pic_proc *var, pic_value val)
 static pic_value
 var_call(pic_state *pic)
 {
-  struct pic_proc *self;
-  pic_value val;
+  pic_value self, val;
   int n;
 
   n = pic_get_args(pic, "&|o", &self, &val);
@@ -48,22 +47,18 @@ var_call(pic_state *pic)
 
     conv = pic_closure_ref(pic, 0);
     if (! pic_false_p(pic, conv)) {
-      val = pic_call(pic, pic_proc_ptr(conv), 1, val);
+      val = pic_call(pic, conv, 1, val);
     }
     return var_set(pic, self, val);
   }
 }
 
-struct pic_proc *
-pic_make_var(pic_state *pic, pic_value init, struct pic_proc *conv)
+pic_value
+pic_make_var(pic_state *pic, pic_value init, pic_value conv)
 {
-  struct pic_proc *var;
-  pic_value c = pic_false_value(pic);
+  pic_value var;
 
-  if (conv != NULL) {
-    c = pic_obj_value(conv);
-  }
-  var = pic_lambda(pic, var_call, 1, c);
+  var = pic_lambda(pic, var_call, 1, conv);
 
   pic_call(pic, var, 1, init);
 
@@ -73,19 +68,17 @@ pic_make_var(pic_state *pic, pic_value init, struct pic_proc *conv)
 static pic_value
 pic_var_make_parameter(pic_state *pic)
 {
-  struct pic_proc *conv = NULL;
-  pic_value init;
+  pic_value init, conv = pic_false_value(pic);
 
   pic_get_args(pic, "o|l", &init, &conv);
 
-  return pic_obj_value(pic_make_var(pic, init, conv));
+  return pic_make_var(pic, init, conv);
 }
 
 static pic_value
 pic_var_with_parameter(pic_state *pic)
 {
-  struct pic_proc *body;
-  pic_value val;
+  pic_value body, val;
 
   pic_get_args(pic, "l", &body);
 
diff --git a/extlib/benz/vector.c b/extlib/benz/vector.c
index da75cd9c..8dce36f3 100644
--- a/extlib/benz/vector.c
+++ b/extlib/benz/vector.c
@@ -224,9 +224,8 @@ pic_vec_vector_fill_i(pic_state *pic)
 static pic_value
 pic_vec_vector_map(pic_state *pic)
 {
-  struct pic_proc *proc;
   int argc, i, len, j;
-  pic_value *argv, vec, vals;
+  pic_value proc, *argv, vec, vals;
 
   pic_get_args(pic, "l*", &proc, &argc, &argv);
 
@@ -249,7 +248,7 @@ pic_vec_vector_map(pic_state *pic)
     for (j = 0; j < argc; ++j) {
       pic_push(pic, pic_vec_ref(pic, argv[j], i), vals);
     }
-    pic_vec_set(pic, vec, i, pic_funcall(pic, "picrin.base", "apply", 2, pic_obj_value(proc), vals));
+    pic_vec_set(pic, vec, i, pic_funcall(pic, "picrin.base", "apply", 2, proc, vals));
   }
 
   return vec;
@@ -258,9 +257,8 @@ pic_vec_vector_map(pic_state *pic)
 static pic_value
 pic_vec_vector_for_each(pic_state *pic)
 {
-  struct pic_proc *proc;
   int argc, i, len, j;
-  pic_value *argv, vals;
+  pic_value proc, *argv, vals;
 
   pic_get_args(pic, "l*", &proc, &argc, &argv);
 
@@ -281,7 +279,7 @@ pic_vec_vector_for_each(pic_state *pic)
     for (j = 0; j < argc; ++j) {
       pic_push(pic, pic_vec_ref(pic, argv[j], i), vals);
     }
-    pic_funcall(pic, "picrin.base", "apply", 2, pic_obj_value(proc), vals);
+    pic_funcall(pic, "picrin.base", "apply", 2, proc, vals);
   }
 
   return pic_undef_value(pic);
diff --git a/extlib/benz/weak.c b/extlib/benz/weak.c
index 86821dae..69effdcc 100644
--- a/extlib/benz/weak.c
+++ b/extlib/benz/weak.c
@@ -105,12 +105,11 @@ weak_set(pic_state *pic, struct pic_weak *weak, void *key, pic_value val)
 static pic_value
 weak_call(pic_state *pic)
 {
-  struct pic_proc *self;
   struct pic_weak *weak;
   pic_value key, val;
   int n;
 
-  n = pic_get_args(pic, "&o|o", &self, &key, &val);
+  n = pic_get_args(pic, "o|o", &key, &val);
 
   if (! pic_obj_p(pic, key)) {
     pic_errorf(pic, "attempted to set a non-object key '~s' in an ephemeron", key);
@@ -128,13 +127,9 @@ weak_call(pic_state *pic)
 static pic_value
 pic_weak_make_ephemeron(pic_state *pic)
 {
-  struct pic_proc *proc;
-
   pic_get_args(pic, "");
 
-  proc = pic_lambda(pic, weak_call, 1, pic_obj_value(pic_make_weak(pic)));
-
-  return pic_obj_value(proc);
+  return pic_lambda(pic, weak_call, 1, pic_obj_value(pic_make_weak(pic)));
 }
 
 void