| <!--{ |
| "Title": "Release History" |
| }--> |
| |
| <p>This page summarizes the changes between official stable releases of Go. |
| Between releases we issue less stable |
| <a href="http://blog.golang.org/2011/03/go-becomes-more-stable.html">weekly snapshots</a>. |
| The <a href="weekly.html">weekly snapshot history</a> contains more detail, |
| and the <a href="http://code.google.com/p/go/source/list">Mercurial change log</a> |
| has full details.</p> |
| |
| <p>To update to a specific release, use:</p> |
| |
| <pre> |
| hg pull |
| hg update <i>tag</i> |
| </pre> |
| |
| <h2 id="go1">go1 (released 2012/03/28)</h2> |
| |
| <p> |
| Go 1 is a major release of Go that will be stable in the long term. |
| Read the <a href="/doc/go1.html">Go 1 Release Notes</a> for more information. |
| </p> |
| |
| <p> |
| It is intended that programs written for Go 1 will continue to compile and run |
| correctly, unchanged, under future versions of Go 1. |
| Read the <a href="/doc/go1compat.html">Go 1 compatibility document</a> for more |
| about the future of Go 1. |
| </p> |
| |
| <p> |
| The go1 release corresponds to |
| <code><a href="weekly.html#2012-03-27">weekly.2012-03-27</a></code>. |
| </p> |
| |
| <h3 id="go1.minor">Minor revisions</h3> |
| |
| <p> |
| go1.0.1 (released 2012/04/25) was issued to |
| <a href="https://code.google.com/p/go/source/detail?r=a890477d3dfb">fix</a> an |
| <a href="https://code.google.com/p/go/issues/detail?id=3545">escape analysis |
| bug</a> that can lead to memory corruption. |
| It also includes several minor code and documentation fixes. |
| </p> |
| |
| <p> |
| go1.0.2 (released 2012/06/13) was issued to fix two bugs in the implementation |
| of maps using struct or array keys: |
| <a href="http://code.google.com/p/go/issues/detail?id=3695">issue 3695</a> and |
| <a href="http://code.google.com/p/go/issues/detail?id=3573">issue 3573</a>. |
| It also includes many minor code and documentation fixes. |
| </p> |
| |
| <p> |
| go1.0.3 (released 2012/09/21) includes minor code and documentation fixes. |
| </p> |
| |
| <p> |
| See the <a href="http://code.google.com/p/go/source/list?name=release-branch.go1">go1 release branch history</a> for the complete list of changes. |
| </p> |
| |
| <h2 id="r60">r60 (released 2011/09/07)</h2> |
| |
| <p> |
| The r60 release corresponds to |
| <code><a href="weekly.html#2011-08-17">weekly.2011-08-17</a></code>. |
| This section highlights the most significant changes in this release. |
| For a more detailed summary, see the |
| <a href="weekly.html#2011-08-17">weekly release notes</a>. |
| For complete information, see the |
| <a href="http://code.google.com/p/go/source/list?r=release-branch.r60">Mercurial change list</a>. |
| </p> |
| |
| <h3 id="r60.lang">Language</h3> |
| |
| <p> |
| An "else" block is now required to have braces except if the body of the "else" |
| is another "if". Since gofmt always puts those braces in anyway, |
| gofmt-formatted programs will not be affected. |
| To fix other programs, run gofmt. |
| </p> |
| |
| <h3 id="r60.pkg">Packages</h3> |
| |
| <p> |
| <a href="/pkg/http/">Package http</a>'s URL parsing and query escaping code |
| (such as <code>ParseURL</code> and <code>URLEscape</code>) has been moved to |
| the new <a href="/pkg/url/">url package</a>, with several simplifications to |
| the names. Client code can be updated automatically with gofix. |
| </p> |
| |
| <p> |
| <a href="/pkg/image/">Package image</a> has had significant changes made to the |
| <code>Pix</code> field of struct types such as |
| <a href="/pkg/image/#RGBA">image.RGBA</a> and |
| <a href="/pkg/image/#NRGBA">image.NRGBA</a>. |
| The <a href="/pkg/image/#Image">image.Image</a> interface type has not changed, |
| though, and you should not need to change your code if you don't explicitly |
| refer to <code>Pix</code> fields. For example, if you decode a number of images |
| using the <a href="/pkg/image/jpeg/">image/jpeg</a> package, compose them using |
| <a href="/pkg/image/draw/">image/draw</a>, and then encode the result using |
| <a href="/pkg/img/png">image/png</a>, then your code should still work as |
| before. |
| If your code <i>does</i> refer to <code>Pix</code> fields see the |
| <a href="/doc/devel/weekly.html#2011-07-19">weekly.2011-07-19</a> |
| snapshot notes for how to update your code. |
| </p> |
| |
| <p> |
| <a href="/pkg/template/">Package template</a> has been replaced with a new |
| templating package (formerly <code>exp/template</code>). The original template |
| package is still available as <a href="/pkg/old/template/">old/template</a>. |
| The <code>old/template</code> package is deprecated and will be removed. |
| The Go tree has been updated to use the new template package. We encourage |
| users of the old template package to switch to the new one. Code that uses |
| <code>template</code> or <code>exp/template</code> will need to change its |
| import lines to <code>"old/template"</code> or <code>"template"</code>, |
| respectively. |
| </p> |
| |
| <h3 id="r60.cmd">Tools</h3> |
| |
| <p> |
| <a href="/cmd/goinstall/">Goinstall</a> now uses a new tag selection scheme. |
| When downloading or updating, goinstall looks for a tag or branch with the |
| <code>"go."</code> prefix that corresponds to the local Go version. For Go |
| <code>release.r58</code> it looks for <code>go.r58</code>. For |
| <code>weekly.2011-06-03</code> it looks for <code>go.weekly.2011-06-03</code>. |
| If the specific <code>go.X</code> tag or branch is not found, it chooses the |
| closest earlier version. If an appropriate tag or branch is found, goinstall |
| uses that version of the code. Otherwise it uses the default version selected |
| by the version control system. Library authors are encouraged to use the |
| appropriate tag or branch names in their repositories to make their libraries |
| more accessible. |
| </p> |
| |
| <h3 id="r60.minor">Minor revisions</h3> |
| |
| <p> |
| r60.1 includes a |
| <a href="http://code.google.com/p/go/source/detail?r=1824581bf62d">linker |
| fix</a>, a pair of |
| <a href="http://code.google.com/p/go/source/detail?r=9ef4429c2c64">goplay</a> |
| <a href="http://code.google.com/p/go/source/detail?r=d42ed8c3098e">fixes</a>, |
| and a <code>json</code> package |
| <a href="http://code.google.com/p/go/source/detail?r=d5e97874fe84">fix</a> and |
| a new |
| <a href="http://code.google.com/p/go/source/detail?r=4f0e6269213f">struct tag |
| option</a>. |
| </p> |
| |
| <p> |
| r60.2 |
| <a href="http://code.google.com/p/go/source/detail?r=ff19536042ac">fixes</a> |
| a memory leak involving maps. |
| </p> |
| |
| <p> |
| r60.3 fixes a |
| <a href="http://code.google.com/p/go/source/detail?r=01fa62f5e4e5">reflect bug</a>. |
| </p> |
| |
| <h2 id="r59">r59 (released 2011/08/01)</h2> |
| |
| <p> |
| The r59 release corresponds to |
| <code><a href="weekly.html#2011-07-07">weekly.2011-07-07</a></code>. |
| This section highlights the most significant changes in this release. |
| For a more detailed summary, see the |
| <a href="weekly.html#2011-07-07">weekly release notes</a>. |
| For complete information, see the |
| <a href="http://code.google.com/p/go/source/list?r=release-branch.r59">Mercurial change list</a>. |
| </p> |
| |
| <h3 id="r59.lang">Language</h3> |
| |
| <p> |
| This release includes a language change that restricts the use of |
| <code>goto</code>. In essence, a <code>goto</code> statement outside a block |
| cannot jump to a label inside that block. Your code may require changes if it |
| uses <code>goto</code>. |
| See <a href="http://code.google.com/p/go/source/detail?r=dc6d3cf9279d">this |
| changeset</a> for how the new rule affected the Go tree. |
| </p> |
| |
| <h3 id="r59.pkg">Packages</h3> |
| |
| <p> |
| As usual, <a href="/cmd/gofix/">gofix</a> will handle the bulk of the rewrites |
| necessary for these changes to package APIs. |
| </p> |
| |
| <p> |
| <a href="/pkg/http">Package http</a> has a new |
| <a href="/pkg/http/#FileSystem">FileSystem</a> interface that provides access |
| to files. The <a href="/pkg/http/#FileServer">FileServer</a> helper now takes a |
| <code>FileSystem</code> argument instead of an explicit file system root. By |
| implementing your own <code>FileSystem</code> you can use the |
| <code>FileServer</code> to serve arbitrary data. |
| </p> |
| |
| <p> |
| <a href="/pkg/os/">Package os</a>'s <code>ErrorString</code> type has been |
| hidden. Most uses of <code>os.ErrorString</code> can be replaced with |
| <a href="/pkg/os/#NewError">os.NewError</a>. |
| </p> |
| |
| <p> |
| <a href="/pkg/reflect/">Package reflect</a> supports a new struct tag scheme |
| that enables sharing of struct tags between multiple packages. |
| In this scheme, the tags must be of the form: |
| </p> |
| <pre> |
| `key:"value" key2:"value2"` |
| </pre> |
| <p> |
| The <a href="/pkg/reflect/#StructField">StructField</a> type's Tag field now |
| has type <a href="/pkg/reflect/#StructTag">StructTag</a>, which has a |
| <code>Get</code> method. Clients of <a href="/pkg/json">json</a> and |
| <a href="/pkg/xml">xml</a> will need to be updated. Code that says |
| </p> |
| <pre> |
| type T struct { |
| X int "name" |
| } |
| </pre> |
| <p> |
| should become |
| </p> |
| <pre> |
| type T struct { |
| X int `json:"name"` // or `xml:"name"` |
| } |
| </pre> |
| <p> |
| Use <a href="/cmd/govet/">govet</a> to identify struct tags that need to be |
| changed to use the new syntax. |
| </p> |
| |
| <p> |
| <a href="/pkg/sort/">Package sort</a>'s <code>IntArray</code> type has been |
| renamed to <a href="/pkg/sort/#IntSlice">IntSlice</a>, and similarly for |
| <a href="/pkg/sort/#Float64Slice">Float64Slice</a> and |
| <a href="/pkg/sort/#StringSlice">StringSlice</a>. |
| </p> |
| |
| <p> |
| <a href="/pkg/strings/">Package strings</a>'s <code>Split</code> function has |
| itself been split into <a href="/pkg/strings/#Split">Split</a> and |
| <a href="/pkg/strings/#SplitN">SplitN</a>. |
| <code>SplitN</code> is the same as the old <code>Split</code>. |
| The new <code>Split</code> is equivalent to <code>SplitN</code> with a final |
| argument of -1. |
| </p> |
| |
| <a href="/pkg/image/draw/">Package image/draw</a>'s |
| <a href="/pkg/image/draw/#Draw">Draw</a> function now takes an additional |
| argument, a compositing operator. |
| If in doubt, use <a href="/pkg/image/draw/#Op">draw.Over</a>. |
| </p> |
| |
| <h3 id="r59.cmd">Tools</h3> |
| |
| <p> |
| <a href="/cmd/goinstall/">Goinstall</a> now installs packages and commands from |
| arbitrary remote repositories (not just Google Code, Github, and so on). |
| See the <a href="/cmd/goinstall/">goinstall documentation</a> for details. |
| </p> |
| |
| <h2 id="r58">r58 (released 2011/06/29)</h2> |
| |
| <p> |
| The r58 release corresponds to |
| <code><a href="weekly.html#2011-06-09">weekly.2011-06-09</a></code> |
| with additional bug fixes. |
| This section highlights the most significant changes in this release. |
| For a more detailed summary, see the |
| <a href="weekly.html#2011-06-09">weekly release notes</a>. |
| For complete information, see the |
| <a href="http://code.google.com/p/go/source/list?r=release-branch.r58">Mercurial change list</a>. |
| </p> |
| |
| <h3 id="r58.lang">Language</h3> |
| |
| <p> |
| This release fixes a <a href="http://code.google.com/p/go/source/detail?r=b720749486e1">use of uninitialized memory in programs that misuse <code>goto</code></a>. |
| </p> |
| |
| <h3 id="r58.pkg">Packages</h3> |
| |
| <p> |
| As usual, <a href="/cmd/gofix/">gofix</a> will handle the bulk of the rewrites |
| necessary for these changes to package APIs. |
| </p> |
| |
| <p> |
| <a href="/pkg/http/">Package http</a> drops the <code>finalURL</code> return |
| value from the <a href="/pkg/http/#Client.Get">Client.Get</a> method. The value |
| is now available via the new <code>Request</code> field on <a |
| href="/pkg/http/#Response">http.Response</a>. |
| Most instances of the type map[string][]string in have been |
| replaced with the new <a href="/pkg/http/#Values">Values</a> type. |
| </p> |
| |
| <p> |
| <a href="/pkg/exec/">Package exec</a> has been redesigned with a more |
| convenient and succinct API. |
| </p> |
| |
| <p> |
| <a href="/pkg/strconv/">Package strconv</a>'s <a href="/pkg/strconv/#Quote">Quote</a> |
| function now escapes only those Unicode code points not classified as printable |
| by <a href="/pkg/unicode/#IsPrint">unicode.IsPrint</a>. |
| Previously Quote would escape all non-ASCII characters. |
| This also affects the <a href="/pkg/fmt/">fmt</a> package's <code>"%q"</code> |
| formatting directive. The previous quoting behavior is still available via |
| strconv's new <a href="/pkg/strconv/#QuoteToASCII">QuoteToASCII</a> function. |
| </p> |
| |
| <p> |
| <a href="/pkg/os/signal/">Package os/signal</a>'s |
| <a href="/pkg/os/#Signal">Signal</a> and |
| <a href="/pkg/os/#UnixSignal">UnixSignal</a> types have been moved to the |
| <a href="/pkg/os/">os</a> package. |
| </p> |
| |
| <p> |
| <a href="/pkg/image/draw/">Package image/draw</a> is the new name for |
| <code>exp/draw</code>. The GUI-related code from <code>exp/draw</code> is now |
| located in the <a href="/pkg/exp/gui/">exp/gui</a> package. |
| </p> |
| |
| <h3 id="r58.cmd">Tools</h3> |
| |
| <p> |
| <a href="/cmd/goinstall/">Goinstall</a> now observes the GOPATH environment |
| variable to build and install your own code and external libraries outside of |
| the Go tree (and avoid writing Makefiles). |
| </p> |
| |
| |
| <h3 id="r58.minor">Minor revisions</h3> |
| |
| <p>r58.1 adds |
| <a href="http://code.google.com/p/go/source/detail?r=293c25943586">build</a> and |
| <a href="http://code.google.com/p/go/source/detail?r=bf17e96b6582">runtime</a> |
| changes to make Go run on OS X 10.7 Lion. |
| </p> |
| |
| <h2 id="r57">r57 (released 2011/05/03)</h2> |
| |
| <p> |
| The r57 release corresponds to |
| <code><a href="weekly.html#2011-04-27">weekly.2011-04-27</a></code> |
| with additional bug fixes. |
| This section highlights the most significant changes in this release. |
| For a more detailed summary, see the |
| <a href="weekly.html#2011-04-27">weekly release notes</a>. |
| For complete information, see the |
| <a href="http://code.google.com/p/go/source/list?r=release-branch.r57">Mercurial change list</a>. |
| </p> |
| |
| <p>The new <a href="/cmd/gofix">gofix</a> tool finds Go programs that use old APIs and rewrites them to use |
| newer ones. After you update to a new Go release, gofix helps make the |
| necessary changes to your programs. Gofix will handle the http, os, and syscall |
| package changes described below, and we will update the program to keep up with |
| future changes to the libraries. |
| Gofix can’t |
| handle all situations perfectly, so read and test the changes it makes before |
| committing them. |
| See <a href="http://blog.golang.org/2011/04/introducing-gofix.html">the gofix blog post</a> for more |
| information.</p> |
| |
| <h3 id="r57.lang">Language</h3> |
| |
| <p> |
| <a href="/doc/go_spec.html#Receive_operator">Multiple assignment syntax</a> replaces the <code>closed</code> function. |
| The syntax for channel |
| receives allows an optional second assigned value, a boolean value |
| indicating whether the channel is closed. This code: |
| </p> |
| |
| <pre> |
| v := <-ch |
| if closed(ch) { |
| // channel is closed |
| } |
| </pre> |
| |
| <p>should now be written as:</p> |
| |
| <pre> |
| v, ok := <-ch |
| if !ok { |
| // channel is closed |
| } |
| </pre> |
| |
| <p><a href="/doc/go_spec.html#Label_scopes">Unused labels are now illegal</a>, just as unused local variables are.</p> |
| |
| <h3 id="r57.pkg">Packages</h3> |
| |
| <p> |
| <a href="/pkg/gob/">Package gob</a> will now encode and decode values of types that implement the |
| <a href="/pkg/gob/#GobEncoder">GobEncoder</a> and |
| <a href="/pkg/gob/#GobDecoder">GobDecoder</a> interfaces. This allows types with unexported |
| fields to transmit self-consistent descriptions; examples include |
| <a href="/pkg/big/#Int.GobDecode">big.Int</a> and <a href="/pkg/big/#Rat.GobDecode">big.Rat</a>. |
| </p> |
| |
| <p> |
| <a href="/pkg/http/">Package http</a> has been redesigned. |
| For clients, there are new |
| <a href="/pkg/http/#Client">Client</a> and <a href="/pkg/http/#Transport">Transport</a> |
| abstractions that give more control over HTTP details such as headers sent |
| and redirections followed. These abstractions make it easy to implement |
| custom clients that add functionality such as <a href="http://code.google.com/p/goauth2/source/browse/oauth/oauth.go">OAuth2</a>. |
| For servers, <a href="/pkg/http/#ResponseWriter">ResponseWriter</a> |
| has dropped its non-essential methods. |
| The Hijack and Flush methods are no longer required; |
| code can test for them by checking whether a specific value implements |
| <a href="/pkg/http/#Hijacker">Hijacker</a> or <a href="/pkg/http/#Flusher">Flusher</a>. |
| The RemoteAddr and UsingTLS methods are replaced by <a href="/pkg/http/#Request">Request</a>'s |
| RemoteAddr and TLS fields. |
| The SetHeader method is replaced by a Header method; |
| its result, of type <a href="/pkg/http/#Header">Header</a>, |
| implements Set and other methods. |
| </p> |
| |
| <p> |
| <a href="/pkg/net/">Package net</a> |
| drops the <code>laddr</code> argument from <a href="/pkg/net/#Conn.Dial">Dial</a> |
| and drops the <code>cname</code> return value |
| from <a href="/pkg/net/#LookupHost">LookupHost</a>. |
| The implementation now uses <a href="/cmd/cgo/">cgo</a> to implement |
| network name lookups using the C library getaddrinfo(3) |
| function when possible. This ensures that Go and C programs |
| resolve names the same way and also avoids the OS X |
| application-level firewall. |
| </p> |
| |
| <p> |
| <a href="/pkg/os/">Package os</a> |
| introduces simplified <a href="/pkg/os/#File.Open">Open</a> |
| and <a href="/pkg/os/#File.Create">Create</a> functions. |
| The original Open is now available as <a href="/pkg/os/#File.OpenFile">OpenFile</a>. |
| The final three arguments to <a href="/pkg/os/#Process.StartProcess">StartProcess</a> |
| have been replaced by a pointer to a <a href="/pkg/os/#ProcAttr">ProcAttr</a>. |
| </p> |
| |
| <p> |
| <a href="/pkg/reflect/">Package reflect</a> has been redesigned. |
| <a href="/pkg/reflect/#Type">Type</a> is now an interface that implements |
| all the possible type methods. |
| Instead of a type switch on a Type <code>t</code>, switch on <code>t.Kind()</code>. |
| <a href="/pkg/reflect/#Value">Value</a> is now a struct value that |
| implements all the possible value methods. |
| Instead of a type switch on a Value <code>v</code>, switch on <code>v.Kind()</code>. |
| Typeof and NewValue are now called <a href="/pkg/reflect/#Type.TypeOf">TypeOf</a> and <a href="/pkg/reflect/#Value.ValueOf">ValueOf</a> |
| To create a writable Value, use <code>New(t).Elem()</code> instead of <code>Zero(t)</code>. |
| See <a href="http://code.google.com/p/go/source/detail?r=843855f3c026">the change description</a> |
| for the full details. |
| The new API allows a more efficient implementation of Value |
| that avoids many of the allocations required by the previous API. |
| </p> |
| |
| <p> |
| Remember that gofix will handle the bulk of the rewrites |
| necessary for these changes to package APIs. |
| </p> |
| |
| <h3 id="r57.cmd">Tools</h3> |
| |
| <p><a href="/cmd/gofix/">Gofix</a>, a new command, is described above.</p> |
| |
| <p> |
| <a href="/cmd/gotest/">Gotest</a> is now a Go program instead of a shell script. |
| The new <code>-test.short</code> flag in combination with package testing's Short function |
| allows you to write tests that can be run in normal or “short” mode; |
| all.bash runs tests in short mode to reduce installation time. |
| The Makefiles know about the flag: use <code>make testshort</code>. |
| </p> |
| |
| <p> |
| The run-time support now implements CPU and memory profiling. |
| Gotest's new |
| <a href="/cmd/gotest/"><code>-test.cpuprofile</code> and |
| <code>-test.memprofile</code> flags</a> make it easy to |
| profile tests. |
| To add profiling to your web server, see the <a href="/pkg/http/pprof/">http/pprof</a> |
| documentation. |
| For other uses, see the <a href="/pkg/runtime/pprof/">runtime/pprof</a> documentation. |
| </p> |
| |
| <h3 id="r57.minor">Minor revisions</h3> |
| |
| <p>r57.1 fixes a <a href="http://code.google.com/p/go/source/detail?r=ff2bc62726e7145eb2ecc1e0f076998e4a8f86f0">nil pointer dereference in http.FormFile</a>.</p> |
| <p>r57.2 fixes a <a href="http://code.google.com/p/go/source/detail?r=063b0ff67d8277df03c956208abc068076818dae">use of uninitialized memory in programs that misuse <code>goto</code></a>.</p> |
| |
| <h2 id="r56">r56 (released 2011/03/16)</h2> |
| |
| <p> |
| The r56 release was the first stable release and corresponds to |
| <code><a href="weekly.html#2011-03-07">weekly.2011-03-07.1</a></code>. |
| The numbering starts at 56 because before this release, |
| what we now consider weekly snapshots were called releases. |
| </p> |