add Module#remove_const

include/mruby/variable.h

@@ -37,6 +37,7 @@ void mrb_vm_const_set(mrb_state*, mrb_sym, mrb_value);
 mrb_value mrb_const_get(mrb_state*, mrb_value, mrb_sym);
 void mrb_const_set(mrb_state*, mrb_value, mrb_sym, mrb_value);
 int mrb_const_defined(mrb_state*, mrb_value, mrb_sym);
+void mrb_const_remove(mrb_state*, mrb_value, mrb_sym);
 
 mrb_value mrb_obj_iv_get(mrb_state *mrb, struct RObject *obj, mrb_sym sym);
 void mrb_obj_iv_set(mrb_state *mrb, struct RObject *obj, mrb_sym sym, mrb_value v);

src/class.c

@@ -1748,6 +1748,20 @@ mrb_mod_const_set(mrb_state *mrb, mrb_value mod)
   return value;
 }
 
+mrb_value
+mrb_mod_remove_const(mrb_state *mrb, mrb_value mod)
+{
+  mrb_sym sym;
+  mrb_value val;
+
+  mrb_get_args(mrb, "n", &sym);
+  check_const_name(mrb, sym);
+  val = mrb_iv_remove(mrb, mod, sym);
+  if (mrb_undef_p(val)) {
+    mrb_name_error(mrb, sym, "instance variable %s not defined", mrb_sym2name(mrb, sym));
+  }
+  return val;
+}
 
 static mrb_value
 mrb_mod_eqq(mrb_state *mrb, mrb_value mod)
@@ -1828,6 +1842,7 @@ mrb_init_class(mrb_state *mrb)
   mrb_define_method(mrb, mod, "const_defined?", mrb_mod_const_defined, ARGS_REQ(1)); /* 15.2.2.4.20 */
   mrb_define_method(mrb, mod, "const_get", mrb_mod_const_get, ARGS_REQ(1));          /* 15.2.2.4.21 */
   mrb_define_method(mrb, mod, "const_set", mrb_mod_const_set, ARGS_REQ(2));          /* 15.2.2.4.23 */
+  mrb_define_method(mrb, mod, "remove_const", mrb_mod_remove_const, ARGS_REQ(1));    /* 15.2.2.4.40 */
   mrb_define_method(mrb, mod, "define_method", mod_define_method, ARGS_REQ(1));
   mrb_define_method(mrb, mod, "class_variables", mrb_mod_class_variables, ARGS_NONE()); /* 15.2.2.4.19 */
 

src/variable.c

@@ -889,7 +889,7 @@ mrb_const_set(mrb_state *mrb, mrb_value mod, mrb_sym sym, mrb_value v)
   mrb_iv_set(mrb, mod, sym, v);
 }
 
-void
+ void
 mrb_vm_const_set(mrb_state *mrb, mrb_sym sym, mrb_value v)
 {
   struct RClass *c = mrb->ci->proc->target_class;
@@ -898,6 +898,13 @@ mrb_vm_const_set(mrb_state *mrb, mrb_sym sym, mrb_value v)
   mrb_obj_iv_set(mrb, (struct RObject*)c, sym, v);
 }
 
+void
+mrb_const_remove(mrb_state *mrb, mrb_value mod, mrb_sym sym)
+{
+  mod_const_check(mrb, mod);
+  mrb_iv_remove(mrb, mod, sym);
+}
+
 void
 mrb_define_const(mrb_state *mrb, struct RClass *mod, const char *name, mrb_value v)
 {