Function find_exprs_in_exprs

datafusion/expr/src/utils.rs:674–690

Search the provided `Expr`'s, and all of their nested `Expr`, for any that pass the provided test. The returned `Expr`'s are deduplicated and returned in order of appearance (depth first).

(
    exprs: impl IntoIterator<Item = &'a Expr>,
    test_fn: &F,
)

/// pass the provided test. The returned `Expr`'s are deduplicated and returned
/// in order of appearance (depth first).
fn find_exprs_in_exprs<'a, F>(
    exprs: impl IntoIterator<Item = &'a Expr>,
    test_fn: &F,
) -> Vec<Expr>
where
    F: Fn(&Expr) -> bool,
{
    exprs
        .into_iter()
        .flat_map(|expr| find_exprs_in_expr(expr, test_fn))
        .fold(vec![], |mut acc, expr| {
            if !acc.contains(&expr) {
                acc.push(expr)
            }
            acc
        })
}

/// Search an `Expr`, and all of its nested `Expr`'s, for any that pass the
/// provided test. The returned `Expr`'s are deduplicated and returned in order