commit 4a13da4bb14be4a1f6b78ee622d0318655855252
Author: Yury Selivanov <yselivanov@sprymix.com>
Date:   Fri Oct 26 18:19:52 2012 -0400

    wip

diff --git a/Doc/tools/sphinxext/layout.html b/Doc/tools/sphinxext/layout.html
index db4a386..ba76ab0 100644
--- a/Doc/tools/sphinxext/layout.html
+++ b/Doc/tools/sphinxext/layout.html
@@ -3,11 +3,19 @@
         <li><img src="{{ pathto('_static/py.png', 1) }}" alt=""
                  style="vertical-align: middle; margin-top: -1px"/></li>
         <li><a href="http://www.python.org/">Python</a>{{ reldelim1 }}</li>
-        <li><a href="{{ pathto('index') }}">{{ shorttitle }}</a>{{ reldelim1 }}</li>
+        <li>
+            {% if pydoc_versionswitcher %}
+                <span id="version_switcher">{{ release }}</span>
+                <a href="{{ pathto('index') }}">Documentation</a>{{ reldelim1 }}
+            {% else %}
+                <a href="{{ pathto('index') }}">{{ shorttitle }}</a>{{ reldelim1 }}
+            {% endif %}
+        </li>
 {% endblock %}
 {% block extrahead %}
     <link rel="shortcut icon" type="image/png" href="{{ pathto('_static/py.png', 1) }}" />
     {% if not embedded %}<script type="text/javascript" src="{{ pathto('_static/copybutton.js', 1) }}"></script>{% endif %}
+    {% if pydoc_versionswitcher %}<script type="text/javascript" src="{{ pathto('_static/version_switch.js', 1) }}"></script>{% endif %}
 {{ super() }}
 {% endblock %}
 {% block footer %}
diff --git a/Doc/tools/sphinxext/pyspecific.py b/Doc/tools/sphinxext/pyspecific.py
index 9b2cc47..95ac0e1 100644
--- a/Doc/tools/sphinxext/pyspecific.py
+++ b/Doc/tools/sphinxext/pyspecific.py
@@ -304,3 +304,8 @@ def setup(app):
     app.add_description_unit('2to3fixer', '2to3fixer', '%s (2to3 fixer)')
     app.add_directive_to_domain('py', 'decorator', PyDecoratorFunction)
     app.add_directive_to_domain('py', 'decoratormethod', PyDecoratorMethod)
+
+    app.add_config_value('pydoc_versionswitcher', False, 'html')
+    def publish_plugin_config(app, pagename, templatename, context, doctree):
+        context['pydoc_versionswitcher'] = app.config.pydoc_versionswitcher
+    app.connect('html-page-context', publish_plugin_config)
diff --git a/Doc/tools/sphinxext/static/version_switch.js b/Doc/tools/sphinxext/static/version_switch.js
new file mode 100644
index 0000000..8be4078
--- /dev/null
+++ b/Doc/tools/sphinxext/static/version_switch.js
@@ -0,0 +1,110 @@
+(function() {
+    'use strict';
+
+    var all_versions = {
+        '3.4': 'dev (3.4)',
+        '3.3': '3.3',
+        '3.2': '3.2',
+        '2.7': '2.7',
+        '2.6': '2.6'
+    };
+
+    function get_version(release) {
+        if (typeof release != 'string' || release.indexOf('.') <= 0) {
+            return;
+        }
+
+        var split = release.split('.');
+        return split[0] + '.' + split[1];
+    }
+
+    function get_doc_versions(current_release) {
+        var version = get_version(current_release),
+            doc_versions = {};
+
+        if (!version) {
+            return;
+        }
+
+        $.each(all_versions, function(version, title) {
+            doc_versions[version] = {
+                title: title
+            };
+        });
+
+        if (doc_versions.hasOwnProperty(version)) {
+            doc_versions[version].title = current_release;
+            doc_versions[version].selected = true;
+
+            return doc_versions;
+        }
+    }
+
+    function build_select(current_release) {
+        var doc_versions = get_doc_versions(current_release),
+            buf = ['<select>'];
+
+        if (!doc_versions) {
+            // Failed to determine the current python version
+            // or some other error
+            return;
+        }
+
+        $.each(doc_versions, function(version, config) {
+            buf.push('<option value="' + version + '"');
+            if (config.selected) {
+                buf.push(' selected="selected"');
+            }
+            buf.push('>' + config.title + '</option>');
+        });
+
+        buf.push('</select>');
+
+        return buf.join('');
+    }
+
+    function patch_url(url, new_version) {
+        var url_re = /\.org\/(py3k|dev|((release\/)?\d\.\d[\w\d\.]*))\//,
+            new_url = url.replace(url_re, '.org/' + new_version + '/');
+
+        if (new_url == url && !new_url.match(url_re)) {
+            // python 2 url without version?
+            new_url = url.replace(/\.org\//, '.org/' + new_version + '/');
+        }
+
+        return new_url;
+    }
+
+    function on_switch() {
+        var selected = null;
+
+        $('#version_switcher option').each(function(index, el) {
+            if (el.selected) {
+                selected = el.value;
+            }
+        });
+
+        var url = window.location.href,
+            new_url = patch_url(url, selected);
+
+        if (new_url != url) {
+            $.get(new_url, function() {
+                // url exists
+                window.location.href = new_url;
+            }).error(function() {
+                window.location.href = 'http://docs.python.org/' + selected;
+            });
+        }
+    }
+
+    $(document).ready(function() {
+        var release_version = DOCUMENTATION_OPTIONS.VERSION,
+            select = build_select(release_version);
+
+        if (select) {
+            $('#version_switcher')
+                .html(select)
+                .bind('change', on_switch);
+        }
+    });
+})();