def over(expr, window):
    prior_op = expr.op()

    if isinstance(prior_op, _ops.WindowOp):
        op = prior_op.over(window)
    else:
        op = _ops.WindowOp(expr, window)

    result = op.to_expr()

    try:
        result = result.name(expr.get_name())
    except:
        pass

    return result
Change counter of ``name`` by ``num`` (can be negative).
dataset/ETHPy150Open cloudera/ibis/ibis/expr/api.py/over--crossover with--dataset/ETHPy150Open tevino/mongu/mongu.py/Counter.change_by