_bytelen = l.bytelen + r.bytelen
end
+ redef fun is_empty do return _bytelen == 0
+
redef fun output do
_left.output
_right.output
from = 0
end
- var ln = length
+ var ln = _length
if (count + from) > ln then count = ln - from
if count <= 0 then return ""
var end_index = from + count - 1