{seek: io.SeekStart, off: 1 << 33, wantpos: 1 << 33, readerr: io.EOF},
		{seek: io.SeekCurrent, off: 1, wantpos: 1<<33 + 1, readerr: io.EOF},
		{seek: io.SeekStart, n: 5, want: "01234"},
		{seek: io.SeekCurrent, n: 5, want: "56789"},
		{seek: io.SeekEnd, off: -1, n: 1, wantpos: 9, want: "9"},
	}

	for i, tt := range tests {
		pos, err := r.Seek(tt.off, tt.seek)
		if err == nil && tt.seekerr != "" {

.DS_Store
*.[56789ao]
*.a[56789o]
*.so
*.pyc
._*
.nfs.*
[56789a].out
*~
*.orig
*.rej
*.exe
.*.swp
core
*.cgo*.go
*.cgo*.c
_cgo_*
_obj
_test
_testmain.go

/VERSION.cache
/bin/
/build.out
/doc/articles/wiki/*.bin
/goinstall.log
/last-change
/misc/cgo/life/run.out
/misc/cgo/stdio/run.out
/misc/cgo/testso/main
/pkg/
/src/*.*/
/src/cmd/cgo/zdefaultcc.go
/src/cmd/dist/dist

		lines(
			"#define A",
			"#ifdef A",
			"#define B 1234",
			"#else",
			"#define B 5678",
			"#endif",
			"B",
		),
		"1234.\n",
	},
	{
		"not taken #ifdef with else",
		lines(
			"#ifdef A",
			"#define B 1234",
			"#else",
			"#define B 5678",
			"#endif",
			"B",
		),
		"5678.\n",
	},
	{
		"nested taken/taken #ifdef",
		lines(
			"#define A",

	[Request]                          # short form, for symbols in the package being documented
	[net/http]                         # package link
	[#12345](/issue/12345)             # GitHub issues
	[CL 6789](/cl/6789)                # Gerrit changelists

To preview `next` content in merged form using a local instance of the website, run:

```
go run golang.org/x/website/cmd/golangorg@latest -goroot=..
```