# `BoundedAuthorityProtocol.V1.ExpectedChain`
[🔗](https://github.com/baselabs/bounded_authority_protocol/blob/v1.0.0/lib/bounded_authority_protocol/v1/expected_chain.ex#L1)

Mandatory caller-derived boundaries for one nonempty consumption-chain range.

Supply these from your own records, never from the rows being checked: a consistent chain cannot
by itself show that no row was removed.

## Fields

* `chain_id` - the chain identity: non-empty StringOrURI of at most `identifier_bytes` (512) UTF-8
  bytes.
* `first_sequence` - the expected sequence number of the first row.
* `last_sequence` - the expected sequence number of the last row.
* `row_count` - the expected number of rows.
* `previous_hash` - the raw 32-byte hash of the row before `first_sequence` (32 zero bytes when it
  is `1`).
* `last_hash` - the raw 32-byte hash of the row at `last_sequence` (the head).
* `bounds` - a `BoundedAuthorityProtocol.V1.Bounds` struct or a map of tightening overrides; `%{}`
  means the profile maxima (see `BoundedAuthorityProtocol.V1.Bounds.coerce/1`).

# `t`

```elixir
@type t() :: %BoundedAuthorityProtocol.V1.ExpectedChain{
  bounds: BoundedAuthorityProtocol.V1.Bounds.t() | map(),
  chain_id: binary(),
  first_sequence: pos_integer(),
  last_hash: binary(),
  last_sequence: pos_integer(),
  previous_hash: binary(),
  row_count: pos_integer()
}
```

Caller boundaries for the façade's `check_chain/2` (for example `BoundedAuthorityProtocol.V1.check_chain/2`).

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*Consult [api-reference.md](api-reference.md) for complete listing*