rb_check_symbol 8 ext/-test-/symbol/init.c return rb_check_symbol(&sym); rb_check_symbol 1448 ext/tk/tkutil/tkutil.c arg_sym = rb_check_symbol(&str); rb_check_symbol 3297 ext/win32ole/win32ole.c sym = rb_check_symbol(&mid); rb_check_symbol 1726 include/ruby/ruby.h VALUE rb_check_symbol(volatile VALUE *namep); rb_check_symbol 832 struct.c idx = rb_check_symbol(name);