Function hash

datafusion/expr/src/higher_order_function.rs:1463–1467

(value: &T)

    }

    fn hash<T: Hash>(value: &T) -> u64 {
        let hasher = &mut DefaultHasher::new();
        value.hash(hasher);
        hasher.finish()
    }

    #[derive(Debug, PartialEq, Eq, Hash)]
    struct MockArrayReduce {