};
        }

        private <Q> Supplier<Q> getMapSupplier(Key<Q> key) {
            Key<?> keyType = key.getTypeParameter(0);
            Key<Object> valueType = key.getTypeParameter(1);
            if (keyType.getRawType() != String.class) {
                throw new DIException("Only String keys are supported for maps: " + key);
            }
            return () -> {

	if req.Name != s.keyID {
		return nil, ErrKeyNotFound
	}

	const randSize = 28
	ciphertext, keyType := parseCiphertext(req.Ciphertext)
	ciphertext, random := ciphertext[:len(ciphertext)-randSize], ciphertext[len(ciphertext)-randSize:]
	iv, nonce := random[:16], random[16:]

	var aead cipher.AEAD
	switch keyType {
	case kms.AES256:
		mac := hmac.New(sha256.New, s.key)
		mac.Write(iv)
		sealingKey := mac.Sum(nil)

called the key type.
The <a href="#Representation_of_values">value</a> of an uninitialized map is <code>nil</code>.
</p>

<pre class="ebnf">
MapType = "map" "[" KeyType "]" ElementType .
KeyType = Type .
</pre>

<p>
The <a href="#Comparison_operators">comparison operators</a>
<code>==</code> and <code>!=</code> must be fully defined