Clarify how "to_ary" and "to_a" work. [ruby-talk:68155]
* eval.c (svalue_to_avalue): ditto.
* eval.c (svalue_to_mrhs): ditto.
* eval.c (rb_eval): unary splat to use to_a, but we need a hack to
exclude Object#to_a until it's removed.
* object.c (rb_Array): check obj.respond_to?("to_a"). Currently
all object respond_to "to_a", but Object#to_a will be removed.
* range.c (Init_Range): undefine to_ary.
* re.c (Init_Regexp): ditto.
* regex.c (re_compile_pattern): do not warn if "-" is at the top
or last of character class.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@3633 b2dd03c8-39d4-4d8f-98ff-823fe69b080e