* @return a peeking iterator backed by that iterator. Apart from the additional {@link
   *     PeekingIterator#peek()} method, this iterator behaves exactly the same as {@code iterator}.
   */
  public static <T extends @Nullable Object> PeekingIterator<T> peekingIterator(
      Iterator<? extends T> iterator) {
    if (iterator instanceof PeekingImpl) {

when you see an instruction like <code>MOV</code>
what the toolchain actually generates for that operation might
not be a move instruction at all, perhaps a clear or load.
Or it might correspond exactly to the machine instruction with that name.
In general, machine-specific operations tend to appear as themselves, while more general concepts like
memory move and subroutine call and return are more abstract.

			// v1.1 does not have CRC.
			if minor < 2 {
				if err := readMore(want); err != nil {
					return nil, err
				}
				return buf[:want], nil
			}

			// CRC is variable length, so we need to truncate exactly that.
			wantMax := min(want+msgp.Uint32Size, size)
			if err := readMore(wantMax); err != nil {
				return nil, err
			}

			if int64(len(buf)) < want {

		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrPOSTFileRequired: {
		Code:           "InvalidArgument",
		Description:    "POST requires exactly one file upload per request.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrSignatureVersionNotSupported: {
		Code:           "InvalidRequest",

	}
}

// Test for golang.org/issue/5947
func TestWriterReadFromWhileFull(t *testing.T) {
	buf := new(bytes.Buffer)
	w := NewWriterSize(buf, 10)

	// Fill buffer exactly.
	n, err := w.Write([]byte("0123456789"))
	if n != 10 || err != nil {
		t.Fatalf("Write returned (%v, %v), want (10, nil)", n, err)
	}

	// Use ReadFrom to read in some data.

    was shutting down.
 *  Fix: Honor `OkHttpClient.retryOnConnectionFailure()` when the response is a
    HTTP 408 Request Timeout. If retries are enabled, OkHttp will retry exactly
    once in response to a 408.
 *  Fix: Don't crash when reading the empty `HEAD` response body if it specifies
    a `Content-Length`.
 *  Fix: Don't crash if the thread is interrupted while reading the public

     * characters in addition to the normal filename characters. The '*'
     * character matches any number of characters in part of a name. If
     * the expression begins with one or more '?'s then exactly that
     * many characters will be matched whereas if it ends with '?'s
     * it will match that many characters <i>or less</i>.
     * <p>
     * Wildcard expressions will not filter workgroup names or server names.

	if len(toMerge) == 0 {
		return policy.Policy{}, errNoSuchPolicy
	}
	return policy.MergePolicies(toMerge...), nil
}

// GetPolicyDoc - gets the policy doc which has the policy and some metadata.
// Exactly one policy must be specified here.
func (store *IAMStoreSys) GetPolicyDoc(name string) (r PolicyDoc, err error) {
	name = strings.TrimSpace(name)
	if name == "" {
		return r, errInvalidArgument
	}

     * characters in addition to the normal filename characters. The '*'
     * character matches any number of characters in part of a name. If
     * the expression begins with one or more '?'s then exactly that
     * many characters will be matched whereas if it ends with '?'s
     * it will match that many characters <i>or less</i>.
     * <p>
     * Wildcard expressions will not filter workgroup names or server names.

	filePath := pathJoin(volumeDir, path)
	if err = checkPathLength(filePath); err != nil {
		return nil, err
	}

	return s.readAllData(ctx, volume, volumeDir, filePath)
}

// ReadFile reads exactly len(buf) bytes into buf. It returns the
// number of bytes copied. The error is EOF only if no bytes were
// read. On return, n == len(buf) if and only if err == nil. n == 0
// for io.EOF.
//