func (k *PrivateKey) ECDH() (*ecdh.PrivateKey, error) {
	c := curveToECDH(k.Curve)
	if c == nil {
		return nil, errors.New("ecdsa: unsupported curve by crypto/ecdh")
	}
	size := (k.Curve.Params().N.BitLen() + 7) / 8
	if k.D.BitLen() > size*8 {
		return nil, errors.New("ecdsa: invalid private key")
	}
	return c.NewPrivateKey(k.D.FillBytes(make([]byte, size)))
}

func curveToECDH(c elliptic.Curve) ecdh.Curve {
	switch c {

flatbuffer_cc_library(
    name = "schema_fbs_with_mutable",
    srcs = ["schema.fbs"],
    compatible_with = get_compatible_with_portable(),
    flatc_args = [
        "--gen-mutable",
        "--gen-object-api",
    ],
    out_prefix = "mutable/",
)

# Generic schema for inference on device (but with reflections makes bigger).
flatbuffer_cc_library(

## Abhängigkeiten für Gruppen von *Pfadoperationen*

    {!> ../../../docs_src/dependencies/tutorial006.py!}
    ```

## Dependencies for a group of *path operations*

Later, when reading about how to structure bigger applications ([Bigger Applications - Multiple Files](../../tutorial/bigger-applications.md){.internal-link target=_blank}), possibly with multiple files, you will learn how to declare a single `dependencies` parameter for a group of *path operations*.

	for i := range s.baseNonce {
		nonce[i] ^= s.baseNonce[i]
	}
	// Message limit is, according to the RFC, 2^95+1, which
	// is somewhat confusing, but we do as we're told.
	if s.seqNum.bitLen() >= (s.aead.NonceSize()*8)-1 {
		panic("message limit reached")
	}
	s.seqNum = s.seqNum.addOne()
	return nonce
}

func (s *Sender) Seal(aad, plaintext []byte) ([]byte, error) {

	m.nat = NewNat().setBig(n)
	m.leading = _W - bitLen(m.nat.limbs[len(m.nat.limbs)-1])
	m.m0inv = minusInverseModW(m.nat.limbs[0])
	m.rr = rr(m)
	return m, nil
}

// bitLen is a version of bits.Len that only leaks the bit length of n, but not
// its value. bits.Len and bits.LeadingZeros use a lookup table for the
// low-order bits on some architectures.
func bitLen(n uint) int {
	var len int

		got    infDecAmount
		expect string
	}{
		{bigDec(big.NewInt(1), 0), "1"},
		{bigDec(big.NewInt(1), 1), "10"},
		{bigDec(big.NewInt(5), 2), "500"},
		{bigDec(big.NewInt(8), 3), "8000"},
		{bigDec(big.NewInt(2), 0), "2"},
		{bigDec(big.NewInt(1), -1), "0.1"},
		{bigDec(big.NewInt(3), -2), "0.03"},
		{bigDec(big.NewInt(4), -3), "0.004"},
		{bigDec(big.NewInt(0).Add(bigMostPositive, big.NewInt(1)), 0), "9223372036854775808"},

// given hash function. salt is a random sequence of bytes whose length will be
// later used to verify the signature.
func signPSSWithSalt(priv *PrivateKey, hash crypto.Hash, hashed, salt []byte) ([]byte, error) {
	emBits := priv.N.BitLen() - 1
	em, err := emsaPSSEncode(hashed, emBits, salt, hash.New())
	if err != nil {
		return nil, err
	}

	if boring.Enabled {
		bkey, err := boringPrivateKey(priv)
		if err != nil {
			return nil, err

    {!> ../../../docs_src/dependencies/tutorial006.py!}
    ```

## Dependencies для группы *операций путей*

Позже, читая о том как структурировать большие приложения ([Bigger Applications - Multiple Files](../../tutorial/bigger-applications.md){.internal-link target=_blank}), возможно, многофайловые, вы узнаете как объявить единый параметр `dependencies` для всей группы *операций путей*.

## Глобальный Dependencies

		check.representable(x, under(x.typ).(*Basic))
		return
	}

	// Untyped integer values must not grow arbitrarily.
	const prec = 512 // 512 is the constant precision
	if x.val.Kind() == constant.Int && constant.BitLen(x.val) > prec {
		op := opName(x.expr)
		if op != "" {
			op += " "
		}
		check.errorf(atPos(opPos), InvalidConstVal, "constant %soverflow", op)
		x.val = constant.MakeUnknown()
	}
}