rjust(*args)
If integer is greater than the length of str, returns a new String of length integer with str right justified and padded with padstr; otherwise, returns str.
"hello".rjust(4) #=> "hello" "hello".rjust(20) #=> " hello" "hello".rjust(20, '1234') #=> "123412341234123hello"
static VALUE rb_str_rjust(int argc, VALUE *argv, VALUE str) { return rb_str_justify(argc, argv, str, 'r'); }