return unicode.IsSpace(r)
}

// Title treats s as UTF-8-encoded bytes and returns a copy with all Unicode letters that begin
// words mapped to their title case.
//
// Deprecated: The rule Title uses for word boundaries does not handle Unicode
// punctuation properly. Use golang.org/x/text/cases instead.
func Title(s []byte) []byte {
	// Use a closure here to remember state.

pkg bufio, method (*Writer) AvailableBuffer() []uint8
pkg bufio, method (ReadWriter) AvailableBuffer() []uint8
pkg bytes, func Cut([]uint8, []uint8) ([]uint8, []uint8, bool)
pkg bytes, func Title //deprecated
pkg crypto/tls, method (*Conn) NetConn() net.Conn
pkg crypto/tls, type Config struct, PreferServerCipherSuites //deprecated
pkg crypto/x509, method (*CertPool) Subjects //deprecated
pkg debug/buildinfo, func Read(io.ReaderAt) (*debug.BuildInfo, error)

---
title: "Go, Backwards Compatibility, and GODEBUG"
layout: article
---

<!--
This document is kept in the Go repo, not x/website,
because it documents the full list of known GODEBUG settings,
which are tied to a specific release.
-->

## Introduction {#intro}

Go's emphasis on backwards compatibility is one of its key strengths.
There are, however, times when we cannot maintain complete compatibility.

}

func ExampleSplitAfterN() {
	fmt.Printf("%q\n", bytes.SplitAfterN([]byte("a,b,c"), []byte(","), 2))
	// Output: ["a," "b,c"]
}

func ExampleTitle() {
	fmt.Printf("%s", bytes.Title([]byte("her royal highness")))
	// Output: Her Royal Highness
}

func ExampleToTitle() {
	fmt.Printf("%s\n", bytes.ToTitle([]byte("loud noises")))
	fmt.Printf("%s\n", bytes.ToTitle([]byte("хлеб")))
	// Output:

<!--{
	"Title": "A Quick Guide to Go's Assembler",
	"Path":  "/doc/asm"
}-->

<h2 id="introduction">A Quick Guide to Go's Assembler</h2>

<p>
This document is a quick outline of the unusual form of assembly language used by the <code>gc</code> Go compiler.
The document is not comprehensive.
</p>

<p>
The assembler is based on the input style of the Plan 9 assemblers, which is documented in detail

<!--{
	"Title": "The Go Memory Model",
	"Subtitle": "Version of June 6, 2022",
	"Path": "/ref/mem"
}-->

<style>
p.rule {
  font-style: italic;
}
</style>

<h2 id="introduction">Introduction</h2>

<p>
The Go memory model specifies the conditions under which
reads of a variable in one goroutine can be guaranteed to
observe values produced by writes to the same variable in a different goroutine.
</p>

<!--{
	"Title": "Go 1.22 Release Notes",
	"Path":  "/doc/go1.22"
}-->

<!--
NOTE: In this document and others in this directory, the convention is to
set fixed-width phrases with non-fixed-width spaces, as in
<code>hello</code> <code>world</code>.
Do not send CLs removing the interior tags from such phrases.
-->

<style>
  main ul li { margin: 0.5em 0; }
</style>

<h2 id="introduction">DRAFT RELEASE NOTES — Introduction to Go 1.22</h2>