diff --git a/src/range.c b/src/range.c
index 7741e90ae..26ec078e8 100644
--- a/src/range.c
+++ b/src/range.c
@@ -508,19 +508,19 @@ mrb_init_range(mrb_state *mrb)
   mrb->range_class = r;
   MRB_SET_INSTANCE_TT(r, MRB_TT_RANGE);
 
-  mrb_define_method(mrb, r, "begin",           range_beg,             MRB_ARGS_NONE()); /* 15.2.14.4.3  */
-  mrb_define_method(mrb, r, "end",             range_end,             MRB_ARGS_NONE()); /* 15.2.14.4.5  */
-  mrb_define_method(mrb, r, "==",              range_eq,              MRB_ARGS_REQ(1)); /* 15.2.14.4.1  */
-  mrb_define_method(mrb, r, "===",             range_include,         MRB_ARGS_REQ(1)); /* 15.2.14.4.2  */
-  mrb_define_method(mrb, r, "exclude_end?",    range_excl,            MRB_ARGS_NONE()); /* 15.2.14.4.6  */
-  mrb_define_method(mrb, r, "first",           range_beg,             MRB_ARGS_NONE()); /* 15.2.14.4.7  */
-  mrb_define_method(mrb, r, "include?",        range_include,         MRB_ARGS_REQ(1)); /* 15.2.14.4.8  */
-  mrb_define_method(mrb, r, "initialize",      range_initialize,      MRB_ARGS_ANY());  /* 15.2.14.4.9  */
-  mrb_define_method(mrb, r, "last",            range_end,             MRB_ARGS_NONE()); /* 15.2.14.4.10 */
-  mrb_define_method(mrb, r, "member?",         range_include,         MRB_ARGS_REQ(1)); /* 15.2.14.4.11 */
-  mrb_define_method(mrb, r, "to_s",            range_to_s,            MRB_ARGS_NONE()); /* 15.2.14.4.12(x) */
-  mrb_define_method(mrb, r, "inspect",         range_inspect,         MRB_ARGS_NONE()); /* 15.2.14.4.13(x) */
-  mrb_define_method(mrb, r, "eql?",            range_eql,             MRB_ARGS_REQ(1)); /* 15.2.14.4.14(x) */
-  mrb_define_method(mrb, r, "initialize_copy", range_initialize_copy, MRB_ARGS_REQ(1)); /* 15.2.14.4.15(x) */
-  mrb_define_method(mrb, r, "__num_to_a",      range_num_to_a,        MRB_ARGS_NONE());
+  mrb_define_method_id(mrb, r, MRB_SYM(begin),           range_beg,             MRB_ARGS_NONE()); /* 15.2.14.4.3  */
+  mrb_define_method_id(mrb, r, MRB_SYM(end),             range_end,             MRB_ARGS_NONE()); /* 15.2.14.4.5  */
+  mrb_define_method_id(mrb, r, MRB_OPSYM(eq),            range_eq,              MRB_ARGS_REQ(1)); /* 15.2.14.4.1  */
+  mrb_define_method_id(mrb, r, MRB_OPSYM(eqq),           range_include,         MRB_ARGS_REQ(1)); /* 15.2.14.4.2  */
+  mrb_define_method_id(mrb, r, MRB_SYM_Q(exclude_end),   range_excl,            MRB_ARGS_NONE()); /* 15.2.14.4.6  */
+  mrb_define_method_id(mrb, r, MRB_SYM(first),           range_beg,             MRB_ARGS_NONE()); /* 15.2.14.4.7  */
+  mrb_define_method_id(mrb, r, MRB_SYM_Q(include),       range_include,         MRB_ARGS_REQ(1)); /* 15.2.14.4.8  */
+  mrb_define_method_id(mrb, r, MRB_SYM(initialize),      range_initialize,      MRB_ARGS_ANY());  /* 15.2.14.4.9  */
+  mrb_define_method_id(mrb, r, MRB_SYM(last),            range_end,             MRB_ARGS_NONE()); /* 15.2.14.4.10 */
+  mrb_define_method_id(mrb, r, MRB_SYM_Q(member),        range_include,         MRB_ARGS_REQ(1)); /* 15.2.14.4.11 */
+  mrb_define_method_id(mrb, r, MRB_SYM(to_s),            range_to_s,            MRB_ARGS_NONE()); /* 15.2.14.4.12(x) */
+  mrb_define_method_id(mrb, r, MRB_SYM(inspect),         range_inspect,         MRB_ARGS_NONE()); /* 15.2.14.4.13(x) */
+  mrb_define_method_id(mrb, r, MRB_SYM_Q(eql),           range_eql,             MRB_ARGS_REQ(1)); /* 15.2.14.4.14(x) */
+  mrb_define_method_id(mrb, r, MRB_SYM(initialize_copy), range_initialize_copy, MRB_ARGS_REQ(1)); /* 15.2.14.4.15(x) */
+  mrb_define_method_id(mrb, r, MRB_SYM(__num_to_a),      range_num_to_a,        MRB_ARGS_NONE());
 }