Prefer rb_check_arity when 0 or 1 arguments

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66179 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

array.c

@@ -2590,13 +2590,7 @@ rb_ary_rotate(VALUE ary, long cnt)
 static VALUE
 rb_ary_rotate_bang(int argc, VALUE *argv, VALUE ary)
 {
-    long n = 1;
-
-    switch (argc) {
-      case 1: n = NUM2LONG(argv[0]);
-      case 0: break;
-      default: rb_scan_args(argc, argv, "01", NULL);
-    }
+    long n = (rb_check_arity(argc, 0, 1) ? NUM2LONG(argv[0]) : 1);
     rb_ary_rotate(ary, n);
     return ary;
 }
@@ -2623,13 +2617,8 @@ rb_ary_rotate_m(int argc, VALUE *argv, VALUE ary)
 {
     VALUE rotated;
     const VALUE *ptr;
-    long len, cnt = 1;
-
-    switch (argc) {
-      case 1: cnt = NUM2LONG(argv[0]);
-      case 0: break;
-      default: rb_scan_args(argc, argv, "01", NULL);
-    }
+    long len;
+    long cnt = (rb_check_arity(argc, 0, 1) ? NUM2LONG(argv[0]) : 1);
 
     len = RARRAY_LEN(ary);
     rotated = rb_ary_new2(len);

complex.c

@@ -1491,7 +1491,7 @@ nucomp_rationalize(int argc, VALUE *argv, VALUE self)
 {
     get_dat1(self);
 
-    rb_scan_args(argc, argv, "01", NULL);
+    rb_check_arity(argc, 0, 1);
 
     if (!k_exact_zero_p(dat->imag)) {
        rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Rational",

rational.c

@@ -2121,7 +2121,7 @@ nilclass_to_r(VALUE self)
 static VALUE
 nilclass_rationalize(int argc, VALUE *argv, VALUE self)
 {
-    rb_scan_args(argc, argv, "01", NULL);
+    rb_check_arity(argc, 0, 1);
     return nilclass_to_r(self);
 }
 
@@ -2150,7 +2150,7 @@ integer_to_r(VALUE self)
 static VALUE
 integer_rationalize(int argc, VALUE *argv, VALUE self)
 {
-    rb_scan_args(argc, argv, "01", NULL);
+    rb_check_arity(argc, 0, 1);
     return integer_to_r(self);
 }
 

re.c

@@ -3960,13 +3960,11 @@ match_setter(VALUE val)
 static VALUE
 rb_reg_s_last_match(int argc, VALUE *argv)
 {
-    VALUE nth;
-
-    if (argc > 0 && rb_scan_args(argc, argv, "01", &nth) == 1) {
+    if (rb_check_arity(argc, 0, 1) == 1) {
         VALUE match = rb_backref_get();
         int n;
         if (NIL_P(match)) return Qnil;
-        n = match_backref_number(match, nth);
+        n = match_backref_number(match, argv[0]);
 	return rb_reg_nth_match(n, match);
     }
     return match_getter();

time.c

@@ -4959,7 +4959,7 @@ time_dump(int argc, VALUE *argv, VALUE time)
 {
     VALUE str;
 
-    rb_scan_args(argc, argv, "01", 0);
+    rb_check_arity(argc, 0, 1);
     str = time_mdump(time);
 
     return str;