The [Alias] type now has an [Rhs] method that returns the type on the
right-hand side of its declaration: given `type A = B`, the `Rhs` of A

</p>

<pre>
A0, A1, and []string
A2 and struct{ a, b int }
A3 and int
A4, func(int, float64) *[]string, and A5

B0 and C0
D0[int, string] and E0
[]int and []int
struct{ a, b *B5 } and struct{ a, b *B5 }
func(x int, y float64) *[]string, func(int, float64) (result *[]string), and A5
</pre>

<p>
<code>B0</code> and <code>B1</code> are different because they are new types

	var buf Buffer
	s := ""
	for i := 0; i < 50; i++ {
		wlen := rand.Intn(len(testString))
		if i%2 == 0 {
			s = fillString(t, "TestMixedReadsAndWrites (1)", &buf, s, 1, testString[0:wlen])
		} else {
			s = fillBytes(t, "TestMixedReadsAndWrites (1)", &buf, s, 1, testBytes[0:wlen])
		}

		rlen := rand.Intn(len(testString))
		fub := make([]byte, rlen)
		n, _ := buf.Read(fub)
		s = s[n:]
	}

	// Hex constant 0xFFFFFFFE00000002 (load of constant on < power10, pli on >= power10
	MOVD $-8589934590, R5           // 3ca00000e8a50000 or 0602000038a00002

	// For backwards compatibility, MOVW $const,Rx and MOVWZ $const,Rx assemble identically
	// and accept the same constants.
	MOVW $2147483648, R5            // 64058000
	MOVWZ $-2147483648, R5          // 3ca08000

corresponding to standard library package paths, and headings for those package
paths will be generated automatically.

Files in this repo's `api/next` directory must have corresponding files in
`doc/next/*stdlib/*minor`.
The files should be in the subdirectory for the package with the new
API, and should be named after the issue number of the API proposal.

`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.
Comparing two `Handle[T]` values is efficient, reducing down to a simple

The new [ParseCookie] function parses a Cookie header value and
returns all the cookies which were set in it. Since the same cookie
name can appear multiple times the returned Values can contain
more than one value for a given key.

The new [ParseSetCookie] function parses a Set-Cookie header value and

targets="$(linux_targets) $(non_linux_targets)"

failed=false
for target in $targets
do
	echo ""
	echo "### Building $target"
	export GOOS=$(echo $target | sed 's/-.*//')
	export GOARCH=$(echo $target | sed 's/.*-//')
	unset GOARM
	if [ "$GOARCH" = "arm5" ]; then
		export GOARCH=arm
		export GOARM=5
	fi

	# Build and vet everything.

analyzer, which flags references to symbols that are too new for the version
of Go in effect in the referring file. (The effective version is determined
by the `go` directive in the file's enclosing `go.mod` file, and
by any [`//go:build` constraints](https://pkg.go.dev/cmd/go#hdr-Build_constraints)
in the file.)

For example, it will report a diagnostic for a reference to the