1 files changed, 2 insertions, 2 deletions
diff --git a/mrbgems/mruby-io/src/io.c b/mrbgems/mruby-io/src/io.c
index 8228097cb..624c27f47 100644
--- a/mrbgems/mruby-io/src/io.c
+++ b/mrbgems/mruby-io/src/io.c
@@ -907,7 +907,7 @@ mrb_io_syswrite(mrb_state *mrb, mrb_value io)
   }
 
   mrb_get_args(mrb, "S", &str);
-  if (mrb_type(str) != MRB_TT_STRING) {
+  if (!mrb_string_p(str)) {
     buf = mrb_funcall(mrb, str, "to_s", 0);
   } else {
     buf = str;
@@ -1000,7 +1000,7 @@ static int
 mrb_io_read_data_pending(mrb_state *mrb, mrb_value io)
 {
   mrb_value buf = mrb_iv_get(mrb, io, mrb_intern_cstr(mrb, "@buf"));
-  if (mrb_type(buf) == MRB_TT_STRING && RSTRING_LEN(buf) > 0) {
+  if (mrb_string_p(buf) && RSTRING_LEN(buf) > 0) {
     return 1;
   }
   return 0;