// in the tests.
func isSpace(r rune) bool {
	if r <= '\u00FF' {
		// Obvious ASCII ones: \t through \r plus space. Plus two Latin-1 oddballs.
		switch r {
		case ' ', '\t', '\n', '\v', '\f', '\r':
			return true
		case '\u0085', '\u00A0':
			return true
		}
		return false
	}
	// High-valued ones.
	if '\u2000' <= r && r <= '\u200a' {
		return true
	}
	switch r {

			t.Fatalf("ReadRune(%U) after UnreadRune got %U,%d not %U,%d (err=%s)", r, r2, nbytes, r, size, err)
		}
	}
}

func TestWriteInvalidRune(t *testing.T) {
	// Invalid runes, including negative ones, should be written as
	// utf8.RuneError.
	for _, r := range []rune{-1, utf8.MaxRune + 1} {
		var buf Buffer
		buf.WriteRune(r)
		check(t, fmt.Sprintf("TestWriteInvalidRune (%d)", r), &buf, "\uFFFD")
	}
}

)

// tagKey returns the tag-based key to use in the pkgCache.
// It is a comma-separated string; the first part is dir, the rest tags.
// The satisfied tags are derived from context but only those that
// matter (the ones listed in the tags argument plus GOOS and GOARCH) are used.
// The tags list, which came from go/build's Package.AllTags,
// is known to be sorted.
func tagKey(dir string, context *build.Context, tags []string) string {

published in PLDI 2008.
The definition of data-race-free programs and the guarantee of sequential consistency
for race-free programs are equivalent to the ones in that work.
</p>

<p>
The memory model describes the requirements on program executions,
which are made up of goroutine executions,
which in turn are made up of memory operations.
</p>

<p>

		// but does not do the following properly:
		//	* It does not treat an empty record as deletion.
		//	* It does not use subsequent global headers to update previous ones.
		//
		//	$ gnutar -tvf pax-global-records.tar
		//	---------- 0/0               0 2017-07-13 19:40 global1
		//	---------- 0/0               0 2017-07-13 19:40 file2
		//	gnutar: Substituting `.' for empty member name