Function all_null

prqlc/prqlc/src/sql/pq/preprocess.rs:500–504

(exprs: Vec<&Expr>)

}

fn all_null(exprs: Vec<&Expr>) -> bool {
    exprs
        .iter()
        .all(|e| matches!(e.kind, ExprKind::Literal(Literal::Null)))
}

/// Converts `(a == b) and ((c == d) and (e == f))`
/// into `([a, c, e], [b, d, f])`