Add `mrb_get_arg1()` that retrieves single (and only) argument.

`mrb_get_arg1()` raises `ArgumentError` if the method does not receive one
argument.

And replaces all `mrb_get_args(mrb, "o", &arg)` by the new function.

1 files changed, 4 insertions, 12 deletions

diff --git a/src/range.c b/src/range.c
index 6df5d13a3..0b4e6dbca 100644
--- a/src/range.c
+++ b/src/range.c
@@ -182,11 +182,9 @@ range_eq(mrb_state *mrb, mrb_value range)
 {
   struct RRange *rr;
   struct RRange *ro;
-  mrb_value obj;
+  mrb_value obj = mrb_get_arg1(mrb);
   mrb_bool v1, v2;
 
-  mrb_get_args(mrb, "o", &obj);
-
   if (mrb_obj_equal(mrb, range, obj)) return mrb_true_value();
   if (!mrb_obj_is_instance_of(mrb, obj, mrb_obj_class(mrb, range))) { /* same class? */
     return mrb_false_value();
@@ -211,13 +209,11 @@ range_eq(mrb_state *mrb, mrb_value range)
 static mrb_value
 range_include(mrb_state *mrb, mrb_value range)
 {
-  mrb_value val;
+  mrb_value val = mrb_get_arg1(mrb);
   struct RRange *r = mrb_range_ptr(mrb, range);
   mrb_value beg, end;
   mrb_bool include_p;
 
-  mrb_get_args(mrb, "o", &val);
-
   beg = RANGE_BEG(r);
   end = RANGE_END(r);
   include_p = r_le(mrb, beg, val) &&                 /* beg <= val */
@@ -289,11 +285,9 @@ range_inspect(mrb_state *mrb, mrb_value range)
 static mrb_value
 range_eql(mrb_state *mrb, mrb_value range)
 {
-  mrb_value obj;
+  mrb_value obj = mrb_get_arg1(mrb);
   struct RRange *r, *o;
 
-  mrb_get_args(mrb, "o", &obj);
-
   if (mrb_obj_equal(mrb, range, obj)) return mrb_true_value();
   if (!mrb_obj_is_kind_of(mrb, obj, mrb->range_class)) return mrb_false_value();
   if (!mrb_range_p(obj)) return mrb_false_value();
@@ -312,11 +306,9 @@ range_eql(mrb_state *mrb, mrb_value range)
 static mrb_value
 range_initialize_copy(mrb_state *mrb, mrb_value copy)
 {
-  mrb_value src;
+  mrb_value src = mrb_get_arg1(mrb);
   struct RRange *r;
 
-  mrb_get_args(mrb, "o", &src);
-
   if (mrb_obj_equal(mrb, copy, src)) return copy;
   if (!mrb_obj_is_instance_of(mrb, src, mrb_obj_class(mrb, copy))) {
     mrb_raise(mrb, E_TYPE_ERROR, "wrong argument class");