Function list_sum 

pub fn list_sum(input: Expression) -> Expression

Creates an expression that sums the elements of each list for List and FixedSizeList inputs, akin to DuckDB’s list_sum().

Follows SQL SUM semantics per list: null lists, empty lists, and lists whose elements are all null yield null; null elements are skipped; integer and decimal overflow yields a null value. The result dtype follows sum’s widening rules and is always nullable. NaN float elements are skipped by default; see list_sum_opts for the NaN-including variant.

let expr = list_sum(root());