[Enh]: Chain operations before .over() for LazyFrames

[naive-forecaster]

We would like to learn about your use case. For example, if this feature is needed to adopt Narwhals in an open source project, could you please enter the link to it below?

No response

Please describe the purpose of the new feature or describe the problem to solve.

I want to create some chained transformations on a column:

nw.col('value').rolling_sum(window_size=10, min_samples=1).shift(2).over('id_col', order_by='date')

But LazyFrames only support some operations like rolling_sum right before an .over(order_by=...).

Would it be possible to make the over apply to all the operations that come before it?

Suggest a solution if possible.

No response

If you have tried alternatives, please describe them below.

I have also tried running an over after each function:

nw.col('value').over('id_col', order_by='date').rolling_sum(window_size=10, min_samples=1).shift(2).over('id_col', order_by='date')

But nested over clauses are not allowed.

Additional information that may help us understand your needs.

No response

[MarcoGorelli]

For now id suggest doing it in two steps

But yes, ideally we would be able to support this. I think