if size != ft.Size {
			t.Errorf("%v: uncompressed size %#x, want %#x", ft.Name, size, ft.Size)
		}
		r.Close()
		return
	}

	var b bytes.Buffer
	_, err = io.Copy(&b, r)
	if err != ft.ContentErr {
		t.Errorf("copying contents: %v (want %v)", err, ft.ContentErr)
	}
	if err != nil {
		return
	}
	r.Close()

	if g := uint64(b.Len()); g != size {

C code may keep a copy of a Go pointer only as long as the memory it
points to is pinned.

C code may not keep a copy of a Go pointer after the call returns,
unless the memory it points to is pinned with [runtime.Pinner] and the
Pinner is not unpinned while the Go pointer is stored in C memory.
This implies that C code may not keep a copy of a string, slice,

<code>len(src)</code> and <code>len(dst)</code>.
As a special case, <code>copy</code> also accepts a destination argument assignable
to type <code>[]byte</code> with a source argument of a string type.
This form copies the bytes from the string into the byte slice.
</p>

<pre class="grammar">
copy(dst, src []T) int
copy(dst []byte, src string) int
</pre>

<p>
Examples:
</p>

<pre>

		for k, v := range h.PAXRecords {
			switch _, exists := paxHdrs[k]; {
			case exists:
				continue // Do not overwrite existing records
			case h.Typeflag == TypeXGlobalHeader:
				paxHdrs[k] = v // Copy all records
			case !basicKeys[k] && !strings.HasPrefix(k, paxGNUSparse):
				paxHdrs[k] = v // Ignore local records that may conflict
			}
		}
		whyOnlyPAX = "only PAX supports PAXRecords"

}

func ExampleBuffer_reader() {
	// A Buffer can turn a string or a []byte into an io.Reader.
	buf := bytes.NewBufferString("R29waGVycyBydWxlIQ==")
	dec := base64.NewDecoder(base64.StdEncoding, buf)
	io.Copy(os.Stdout, dec)
	// Output: Gophers rule!
}

func ExampleBuffer_Bytes() {
	buf := bytes.Buffer{}
	buf.Write([]byte{'h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd'})
	os.Stdout.Write(buf.Bytes())

	POPCNTB R3, R4                  // 7c6400f4
	POPCNTW R3, R4                  // 7c6402f4
	POPCNTD R3, R4                  // 7c6403f4

	PASTECC R3, R4                  // 7c23270d
	COPY R3, R4                     // 7c23260c

	// load-and-reserve
	LBAR (R4)(R3*1),$1,R5           // 7ca32069
	LBAR (R4)(R0),$1,R5             // 7ca02069
	LBAR (R4),$0,R5                 // 7ca02068

		return 0, errDiscardedBytes
	}
	suf := ss.Suffix()
	n = copy(p, suf[len(suf)-int(back):])
	if n != len(p) {
		err = io.EOF
	}
	return
}

func (ss *suffixSaver) Suffix() []byte {
	if len(ss.buf) < ss.keep {
		return ss.buf
	}
	buf := make([]byte, ss.keep)
	n := copy(buf, ss.buf[ss.start:])
	copy(buf[n:], ss.buf[:])
	return buf
}

canonicalizing values (like "interning" or "hash-consing").

Any value of comparable type may be canonicalized with the new
`Make[T]` function, which produces a reference to a canonical copy of
the value in the form of a `Handle[T]`.
Two `Handle[T]` are equal if and only if the values used to produce the
handles are equal, allowing programs to deduplicate values and reduce
their memory footprint.

func append(slice []Type, elems ...Type) []Type

// The copy built-in function copies elements from a source slice into a
// destination slice. (As a special case, it also will copy bytes from a
// string to a slice of bytes.) The source and destination may overlap. Copy
// returns the number of elements copied, which will be the minimum of
// len(src) and len(dst).
func copy(dst, src []Type) int

As a special case, if the destination's core type is <code>[]byte</code>,
<code>copy</code> also accepts a source argument with core type
<a href="#Core_types"><code>bytestring</code></a>.
This form copies the bytes from the byte slice or string into the byte slice.
</p>

<pre class="grammar">
copy(dst, src []T) int
copy(dst []byte, src string) int
</pre>

<p>
Examples:
</p>

<pre>