add pic_func struct to hold native function name

src/gc.c

@@ -356,7 +356,7 @@ gc_mark_object(pic_state *pic, struct pic_object *obj)
     if (proc->env) {
       gc_mark_object(pic, (struct pic_object *)proc->env);
     }
-    if (! proc->cfunc_p) {
+    if (pic_proc_irep_p(proc)) {
       gc_mark_object(pic, (struct pic_object *)proc->u.irep);
     }
     break;

src/proc.c

@@ -8,13 +8,14 @@
 #include "picrin/irep.h"
 
 struct pic_proc *
-pic_proc_new(pic_state *pic, pic_func_t cfunc)
+pic_proc_new(pic_state *pic, pic_func_t func)
 {
   struct pic_proc *proc;
 
   proc = (struct pic_proc *)pic_obj_alloc(pic, sizeof(struct pic_proc), PIC_TT_PROC);
-  proc->cfunc_p = true;
-  proc->u.cfunc = cfunc;
+  proc->kind = PIC_PROC_KIND_FUNC;
+  proc->u.func.f = func;
+  proc->u.func.name = pic_intern_cstr(pic, "(no name)");
   proc->env = NULL;
   return proc;
 }
@@ -25,7 +26,7 @@ pic_proc_new_irep(pic_state *pic, struct pic_irep *irep, struct pic_env *env)
   struct pic_proc *proc;
 
   proc = (struct pic_proc *)pic_obj_alloc(pic, sizeof(struct pic_proc), PIC_TT_PROC);
-  proc->cfunc_p = false;
+  proc->kind = PIC_PROC_KIND_IREP;
   proc->u.irep = irep;
   proc->env = env;
   return proc;

src/var.c

@@ -50,7 +50,10 @@ get_var_from_proc(pic_state *pic, struct pic_proc *proc)
 {
   pic_value v;
 
-  if (! proc->cfunc_p) {
+  if (! pic_proc_p(v)) {
+    goto typeerror;
+  }
+  if (! pic_proc_func_p(pic_proc_ptr(v))) {
     goto typeerror;
   }
   if (pic_proc_cv_size(pic, proc) != 1) {

src/vm.c

@@ -480,7 +480,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, pic_value argv)
         pic_error(pic, "logic flaw");
       }
       irep = pic_proc_ptr(self)->u.irep;
-      if (pic_proc_cfunc_p(self)) {
+      if (! pic_proc_irep_p(pic_proc_ptr(self))) {
         pic_error(pic, "logic flaw");
       }
       PUSH(irep->pool[c.u.i]);
@@ -590,10 +590,10 @@ pic_apply(pic_state *pic, struct pic_proc *proc, pic_value argv)
       ci->ip = pic->ip;
       ci->fp = pic->sp - c.u.i;
       ci->env = NULL;
-      if (pic_proc_cfunc_p(x)) {
+      if (pic_proc_func_p(pic_proc_ptr(x))) {
 
         /* invoke! */
-	pic->sp[0] = proc->u.cfunc(pic);
+	pic->sp[0] = proc->u.func.f(pic);
         pic->sp += ci->retc;
 
         pic_gc_arena_restore(pic, ai);
@@ -702,7 +702,7 @@ pic_apply(pic_state *pic, struct pic_proc *proc, pic_value argv)
         pic_error(pic, "logic flaw");
       }
       irep = pic_proc_ptr(self)->u.irep;
-      if (pic_proc_cfunc_p(self)) {
+      if (! pic_proc_irep_p(pic_proc_ptr(self))) {
         pic_error(pic, "logic flaw");
       }
       proc = pic_proc_new_irep(pic, irep->irep[c.u.i], pic->ci->env);