tmp := make([]byte, 5)
	for i := 0; i <= 5; i++ {
		for j := i; j <= 5; j++ {
			for k := 0; k <= 6; k++ {
				// 0 <= i <= j <= 5; 0 <= k <= 6
				// Check that if we start with a buffer
				// of length j at offset i and ask for
				// Next(k), we get the right bytes.
				buf := NewBuffer(b[0:j])
				n, _ := buf.Read(tmp[0:i])
				if n != i {
					t.Fatalf("Read %d returned %d", i, n)
				}
				bb := buf.Next(k)

(discussed below).

When preparing any change that is permitted by Go 1 compatibility
but may nonetheless break some existing programs,
we first engineer the change to keep as many existing programs working as possible.
For the remaining programs,
we define a new GODEBUG setting that
allows individual programs to opt back in to the old behavior.
A GODEBUG setting may not be added if doing so is infeasible,

spaces) and may also exclude the characters
<code>!"#$%&amp;'()*,:;&lt;=&gt;?[\]^`{|}</code>
and the Unicode replacement character U+FFFD.
</p>

<p>
Assume we have compiled a package containing the package clause
<code>package math</code>, which exports function <code>Sin</code>, and
installed the compiled package in the file identified by
<code>"lib/math"</code>.

// to avoid misleading negative results.
// This makes all the references to os.FileInfo in go1.txt
// be read as if they said fs.FileInfo, since os.FileInfo is now an alias.
// If there are many of these, we could do a more general solution,
// but for now the replacer is fine.
var aliasReplacer = strings.NewReplacer(
	"os.FileInfo", "fs.FileInfo",
	"os.FileMode", "fs.FileMode",
	"os.PathError", "fs.PathError",
)

[T int|string]               // = [T interface{int|string}]
type Constraint ~int         // illegal: ~int is not in a type parameter list
</pre>

<!--
We should be able to simplify the rules for comparable or delegate some of them
elsewhere since we have a section that clearly defines how interfaces implement
other interfaces based on their type sets. But this should get us going for now.
-->

<p>