allows individual programs to opt back in to the old behavior.
A GODEBUG setting may not be added if doing so is infeasible,
but that should be extremely rare.

GODEBUG settings added for compatibility will be maintained
for a minimum of two years (four Go releases).
Some, such as `http2client` and `http2server`,
will be maintained much longer, even indefinitely.

When possible, each GODEBUG setting has an associated

then an `api/next` file with the line

    pkg net/http, function F #12345

should have a corresponding file named `doc/next/6-stdlib/99-minor/net/http/12345.md`.
At a minimum, that file should contain either a full sentence or a TODO,
ideally referring to a person with the responsibility to complete the note.

Use the following forms in your markdown:

// 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

// The delete built-in function deletes the element with the specified key
// (m[key]) from the map. If m is nil or there is no such element, delete

Both arguments must have <a href="#Type_identity">identical</a> element type <code>T</code> and must be
<a href="#Assignability">assignable</a> to a slice of type <code>[]T</code>.
The number of elements copied is the minimum of
<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.

language.
</p>

<p>
A link of the form [<a href="#Language_versions">Go 1.xx</a>] indicates that a described
language feature (or some aspect of it) was changed or added with language version 1.xx and
thus requires at minimum that language version to build.
For details, see the <a href="#Language_versions">linked section</a>
in the <a href="#Appendix">appendix</a>.
</p>

<h2 id="Source_code_representation">Source code representation</h2>

func Compare(a, b []byte) int {
	return bytealg.Compare(a, b)
}

// explode splits s into a slice of UTF-8 sequences, one per Unicode code point (still slices of bytes),
// up to a maximum of n byte slices. Invalid UTF-8 sequences are chopped into individual bytes.
func explode(s []byte, n int) [][]byte {
	if n <= 0 || n > len(s) {
		n = len(s)
	}
	a := make([][]byte, n)
	var size int
	na := 0

It allows a counting semaphore to be modeled by a buffered channel:
the number of items in the channel corresponds to the number of active uses,
the capacity of the channel corresponds to the maximum number of simultaneous uses,
sending an item acquires the semaphore, and receiving an item releases
the semaphore.
This is a common idiom for limiting concurrency.
</p>

<p>