doc/go1.4.html: first pieces of release notes

Move the release notes into an HTML file.
Start writing the text.

LGTM=rsc
R=golang-codereviews, bradfitz, kamil.kisiel, tracey.brendan, rsc
CC=golang-codereviews
https://golang.org/cl/161350043

doc/go1.4.txt → doc/go1.4.html

-This file collects notes about what has changed since Go 1.3
-and should be mentioned in the Go 1.4 release notes.
+<!--{
+	"Title": "Go 1.4 Release Notes",
+	"Path":  "/doc/go1.4",
+	"Template": true
+}-->
 
-Please keep the descriptions to a single line, starting with the
-package or cmd/xxx directory name, and ending in a CL number.
-Please keep the list sorted (as in sort.Strings of the lines).
+<h2 id="introduction">Introduction to Go 1.4</h2>
 
-spec: permit for range x (CL 104680043)
+<p>
+The latest Go release, version 1.4, arrives as scheduled six months after 1.3
+and contains only one tiny language change,
+a backwards-compatible simple form of <code>for</code>-<code>range</code> loop.
+The release focuses primarily on implementation work, improving the garbage collector
+and preparing the ground for a fully concurrent collector to be rolled out in the
+next few releases.
+Stacks are now contiguous, reallocated when necessary rather than linking on new
+"segments";
+this release therefore eliminates the notorious "hot stack split" problem.
+There are some new tools available including support in the <code>go</code> command
+for build-time source code generation
+and TODO.
+The release also adds support for TODO architecture and TODO operating systems.
+As always, Go 1.4 keeps the <a href="/doc/go1compat.html">promise
+of compatibility</a>,
+and almost everything 
+will continue to compile and run without change when moved to 1.4.
+</p>
+
+<h2 id="language">Changes to the language</h2>
+
+<h3 id="forrange">For-range loops</h3>
+<p>
+Up until Go 1.3, <code>for</code>-<code>range</code> loop had two forms
+</p>
+
+<pre>
+for k, v := range x {
+	...
+}
+</pre>
+
+<p>
+and
+</p>
+
+<pre>
+for k := range x {
+	...
+}
+</pre>
+
+<p>
+If one was not interested in the loop values, only the iteration itself, it was still
+necessary to mention a variable (probably the <a href="/ref/spec#Blank_identifier">blank identifier</a>, as in
+<code>for</code> <code>_</code> <code>=</code> <code>range</code> <code>x</code>), because
+the form
+</p>
+
+<pre>
+for range x {
+	...
+}
+</pre>
+
+<p>
+was not syntactically permitted.
+</p>
+
+<p>
+This situation seemed awkward, so as of Go 1.4 the variable-free form is now legal.
+The situation arises only rarely but the code can be cleaner when it does.
+</p>
+
+<p>
+<em>Updating</em>: The change is strictly backwards compatible to existing Go
+programs, but tools that analyze Go parse trees may need to be modified to accept
+this new form as the
+<code>Key</code> field of <a href="/pkg/go/ast/#RangeStmt"><code>RangeStmt</code></a>
+may now be <code>nil</code>.
+</p>
+
+<h2 id="os">Changes to the supported operating systems and architectures</h2>
+
+<h3 id="foobarblatz">FooBarBlatz</h3>
+
+<p>
+TODO news about foobarblatz
+</p>
+
+<h2 id="compatibility">Changes to the compatibility guidelines</h2>
+
+<p>
+The <a href="/pkg/unsafe/"><code>unsafe</code></a> package allows one
+to defeat Go's type system by exploiting internal details of the implementation
+or machine representation of data.
+It was never explicitly specified what use of <code>unsafe</code> meant
+with respect to compatibility as specified in the
+<a href="go1compat.html">Go compatibilty guidelines</a>.
+The answer, of course, is that we can make no promise of compatibility
+for code that does unsafe things.
+</p>
+
+<p>
+We have clarified this situation in the documentation included in the release.
+The <a href="go1compat.html">Go compatibilty guidelines</a> and the
+docs for the <a href="/pkg/unsafe/"><code>unsafe</code></a> package
+are now explicit that unsafe code is not guaranteed to remain compatible.
+</p>
+  
+<p>
+<em>Updating</em>: Nothing technical has changed; this is just a clarification
+of the documentation.
+</p>
+
+
+<h2 id="impl">Changes to the implementations and tools</h2>
+
+<h3 id="garbage_collector">Changes to the garbage collector</h3>
+
+<p>
+TODO news about garbage collection
+</p>
+
+<h3 id="stacks">Stack</h3>
+
+<p>
+TODO news about stacks
+</p>
+
+<h3 id="gccgo">Status of gccgo</h3>
+
+<p>
+TODO gccgo news
+</p>
+
+<h3 id="gocmd">Changes to the go command</h3>
+
+<p>
+TODO go command news
+</p>
+
+<h3 id="cgo">Changes to cgo</h3>
+
+<p>
+TODO cgo news
+</p>
+
+
+<h3 id="godoc">Changes to godoc</h3>
+<p>
+TODO godoc news
+</p>
+
+<h3 id="pkg">Changes to package source layout</h3>
+
+<p>
+In the main Go source repository, the source code for the packages was kept in
+the directory <code>src/pkg</code>, which made sense but differed from
+other repositories, including the Go sub-repositories such as <code>go.tools</code>.
+In Go 1.4, the<code> pkg</code> level of the source tree is now gone, so for example
+the <a href="/pkg/fmt/"><code>fmt</code></a> package's source, once kept in
+directory <code>src/pkg/fmt</code>, now lives one level higher in <code>src/fmt</code>.
+</p>
+
+<p>
+<em>Updating</em>: Tools like <code>godoc</code> that discover source code
+need to know about the new location. All tools and services maintained by the Go team
+have been updated.
+</p>
+
+<h3 id="misc">Miscellany</h3>
+
+<p>
+TODO misc news
+</p>
+
+<h2 id="performance">Performance</h2>
+
+<p>
+TODO performance news
+</p>
+
+<h2 id="library">Changes to the standard library</h2>
+
+<h3 id="new_packages">New packages</h3>
+
+<p>
+TODO new packages
+</p>
+
+<h3 id="major_library_changes">Major changes to the library</h3>
+
+<p>
+TODO major changes
+</p>
+
+<h3 id="minor_library_changes">Minor changes to the library</h3>
+
+<p>
+The following list summarizes a number of minor changes to the library, mostly additions.
+See the relevant package documentation for more information about each change.
+</p>
+
+<ul>
+
+<li> TODO changes
+</li>
+</ul>
+
+<pre>
 
 the directory src/pkg has been deleted, for instance src/pkg/fmt is now just src/fmt (CL 134570043)
 
@@ -26,7 +228,7 @@ crypto/tls: add support for ALPN (RFC 7301) (CL 108710046)
 crypto/tls: support programmatic selection of server certificates (CL 107400043)
 encoding/asn1: optional elements with a default value will now only be omitted if they have that value (CL 86960045)
 flag: it is now an error to set a flag multiple times (CL 156390043)
-fmt: print type *map[T]T as &map[k:v] (CL 154870043)
+fmt: print type *map[T]T as &amp;map[k:v] (CL 154870043)
 encoding/csv: do not quote empty strings, quote \. (CL 164760043)
 encoding/gob: remove unsafe (CL 102680045)
 misc: deleted editor support; refer to https://code.google.com/p/go-wiki/wiki/IDEsAndTextEditorPlugins instead (CL 105470043)
@@ -51,3 +253,4 @@ time: use the micro symbol (µ (U+00B5)) to print microsecond duration (CL 10503
 unsafe: document the existing situation that unsafe programs are not go1-guaranteed (CL 162060043)
 
 go.sys subrepo created: http://golang.org/s/go1.4-syscall
+</pre>