ssz_types 0.14.1

List, vector and bitfield types for SSZ
Documentation 
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use tree_hash::{Hash256, MerkleHasher, TreeHash, TreeHashType};

/// A helper function providing common functionality between the `TreeHash` implementations for
/// `FixedVector` and `VariableList`.
pub fn vec_tree_hash_root<T>(vec: &[T], max_leaves: usize) -> Hash256
where
    T: TreeHash,
{
    match T::tree_hash_type() {
        TreeHashType::Basic => {
            let mut hasher =
                MerkleHasher::with_leaves(max_leaves.div_ceil(T::tree_hash_packing_factor()));

            for item in vec {
                hasher
                    .write(&item.tree_hash_packed_encoding())
                    .expect("ssz_types variable vec should not contain more elements than max");
            }

            hasher
                .finish()
                .expect("ssz_types variable vec should not have a remaining buffer")
        }
        TreeHashType::Container | TreeHashType::List | TreeHashType::Vector => {
            let mut hasher = MerkleHasher::with_leaves(max_leaves);

            for item in vec {
                hasher
                    .write(item.tree_hash_root().as_slice())
                    .expect("ssz_types vec should not contain more elements than max");
            }

            hasher
                .finish()
                .expect("ssz_types vec should not have a remaining buffer")
        }
    }
}