# `BSV.Tokens.SigningKey`
[🔗](https://github.com/Bittoku/bsv_sdk_elixir/blob/main/lib/bsv/tokens/signing_key.ex#L1)

Signing credentials for a UTXO — either a single key (P2PKH) or
threshold keys with a multisig script (P2MPKH).

## Variants

    {:single, PrivateKey.t()}
    {:multi, [PrivateKey.t()], P2MPKH.multisig_script()}

## Examples

    # P2PKH signing
    signing_key = SigningKey.single(private_key)

    # 2-of-3 P2MPKH signing
    {:ok, ms} = P2MPKH.new_multisig(2, [pk1, pk2, pk3])
    signing_key = SigningKey.multi([key1, key2], ms)

# `t`

```elixir
@type t() ::
  {:single, BSV.PrivateKey.t()}
  | {:multi, [BSV.PrivateKey.t()], BSV.Transaction.P2MPKH.multisig_script()}
```

# `hash160`

```elixir
@spec hash160(t()) :: <<_::160>>
```

Compute the 20-byte hash for this signing key.

- P2PKH: HASH160 of compressed public key
- P2MPKH: HASH160 of serialized multisig script (the MPKH)

# `multi`

```elixir
@spec multi([BSV.PrivateKey.t()], BSV.Transaction.P2MPKH.multisig_script()) :: t()
```

Create a P2MPKH signing key.

# `multi?`

```elixir
@spec multi?(t()) :: boolean()
```

Returns `true` if this is a P2MPKH signing key.

# `single`

```elixir
@spec single(BSV.PrivateKey.t()) :: t()
```

Create a P2PKH signing key.

# `wrap`

```elixir
@spec wrap(BSV.PrivateKey.t() | t()) :: t()
```

Wrap a `PrivateKey` as a signing key (convenience for migration).

Accepts either a `PrivateKey` struct or an existing `SigningKey` tuple.

---

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