> Aztec.nr API reference, v6.0.0 (mainnet and testnet). Index: https://docs.aztec.network/aztec-nr-api/v6.0.0/llms.txt

# Function are_block_hashes_in_archive

Module: `noir_aztec::oracle::get_membership_witness`

```rust
pub unconstrained fn are_block_hashes_in_archive(
    anchor_block_header: BlockHeader,
    block_hashes: EphemeralArray<Field>,
) -> EphemeralArray<bool>
```

Returns whether each block hash is present in the archive tree whose root is defined in `anchor_block_header`.