Implement `Range#last` in `mruby-range-ext` in Ruby.
This reduce unnecessary calls of `mrb_funcall()`.
MODIFY
mrbgems/mruby-range-ext/mrblib/range.rb
mrbgems/mruby-range-ext/mrblib/range.rb
@@ -26,6 +26,32 @@ class Range
ary
end
+ ##
+ # call-seq:
+ # rng.last -> obj
+ # rng.last(n) -> an_array
+ #
+ # Returns the last object in the range,
+ # or an array of the last +n+ elements.
+ #
+ # Note that with no arguments +last+ will return the object that defines
+ # the end of the range even if #exclude_end? is +true+.
+ #
+ # (10..20).last #=> 20
+ # (10...20).last #=> 20
+ # (10..20).last(3) #=> [18, 19, 20]
+ # (10...20).last(3) #=> [17, 18, 19]
+ def last(*args)
+ raise RangeError, "cannot get the first element of beginless range" if self.end.nil?
+ return self.end if args.empty?
+
+ raise ArgumentError, "wrong number of arguments (given #{args.length}, expected 1)" unless args.length == 1
+ nv = args[0]
+ n = nv.__to_int
+ raise ArgumentError, "negative array size (or size too big)" unless 0 <= n
+ return self.to_a.last(nv)
+ end
+
def max(&block)
val = self.begin
last = self.end

MODIFY
mrbgems/mruby-range-ext/src/range.c
mrbgems/mruby-range-ext/src/range.c
@@ -58,41 +58,6 @@ range_cover(mrb_state *mrb, mrb_value range)
return mrb_false_value();
}
-/*
- * call-seq:
- * rng.last -> obj
- * rng.last(n) -> an_array
- *
- * Returns the last object in the range,
- * or an array of the last +n+ elements.
- *
- * Note that with no arguments +last+ will return the object that defines
- * the end of the range even if #exclude_end? is +true+.
- *
- * (10..20).last #=> 20
- * (10...20).last #=> 20
- * (10..20).last(3) #=> [18, 19, 20]
- * (10...20).last(3) #=> [17, 18, 19]
- */
-static mrb_value
-range_last(mrb_state *mrb, mrb_value range)
-{
- mrb_value num;
- mrb_value array;
- struct RRange *r = mrb_range_ptr(mrb, range);
-
- if (mrb_nil_p(RANGE_END(r))) {
- mrb_raise(mrb, E_RANGE_ERROR, "cannot get the last element of endless range");
- }
-
- if (mrb_get_args(mrb, "|o", &num) == 0) {
- return mrb_range_end(mrb, range);
- }
-
- array = mrb_funcall_id(mrb, range, MRB_SYM(to_a), 0);
- return mrb_funcall_id(mrb, array, MRB_SYM(last), 1, mrb_to_int(mrb, num));
-}
-
/*
* call-seq:
* rng.size -> num
@@ -194,7 +159,6 @@ mrb_mruby_range_ext_gem_init(mrb_state* mrb)
struct RClass * s = mrb_class_get(mrb, "Range");
mrb_define_method(mrb, s, "cover?", range_cover, MRB_ARGS_REQ(1));
- mrb_define_method(mrb, s, "last", range_last, MRB_ARGS_OPT(1));
mrb_define_method(mrb, s, "size", range_size, MRB_ARGS_NONE());
}

Implement `Range#last` in `mruby-range-ext` in Ruby.

This reduce unnecessary calls of `mrb_funcall()`.