fix: Added lang variable for guide links

_includes/api/en/4x/app-METHOD.md

@@ -59,4 +59,4 @@ The method, `app.all()`, is not derived from any HTTP method and loads middlewar
 the specified path for _all_ HTTP request methods.
 For more information, see [app.all](#app.all).
 
-For more information on routing, see the [routing guide](/guide/routing.html).
+For more information on routing, see the [routing guide](/{{page.lang}}/guide/routing.html).

_includes/api/en/4x/app-delete-method.md

@@ -1,7 +1,7 @@
 <h3 id='app.delete.method'>app.delete(path, callback [, callback ...])</h3>
 
 Routes HTTP DELETE requests to the specified path with the specified callback functions.
-For more information, see the [routing guide](/guide/routing.html).
+For more information, see the [routing guide](/{{page.lang}}/guide/routing.html).
 
 {% include api/en/4x/routing-args.html %}
 

_includes/api/en/4x/app-get-method.md

@@ -4,7 +4,7 @@ Routes HTTP GET requests to the specified path with the specified callback funct
 
 {% include api/en/4x/routing-args.html %}
 
-For more information, see the [routing guide](/guide/routing.html).
+For more information, see the [routing guide](/{{page.lang}}/guide/routing.html).
 
 #### Example
 

_includes/api/en/4x/app-post-method.md

@@ -1,7 +1,7 @@
 <h3 id='app.post.method'>app.post(path, callback [, callback ...])</h3>
 
 Routes HTTP POST requests to the specified path with the specified callback functions.
-For more information, see the [routing guide](/guide/routing.html).
+For more information, see the [routing guide](/{{page.lang}}/guide/routing.html).
 
 {% include api/en/4x/routing-args.html %}
 

_includes/api/en/4x/app-settings.md

@@ -198,7 +198,7 @@ A custom query string parsing function will receive the complete query string, a
  <h5 id="trust.proxy.options.table">Options for `trust proxy` setting</h5>
 
  <p markdown="1">
- Read [Express behind proxies](/guide/behind-proxies.html) for more
+ Read [Express behind proxies](/{{page.lang}}/guide/behind-proxies.html) for more
  information.
  </p>
 

_includes/api/en/4x/app-use.md

@@ -1,6 +1,6 @@
 <h3 id='app.use'>app.use([path,] callback [, callback...])</h3>
 
-Mounts the specified [middleware](/guide/using-middleware.html) function or functions
+Mounts the specified [middleware](/{{page.lang}}/guide/using-middleware.html) function or functions
 at the specified path:
 the middleware function is executed when the base of the requested path matches `path`.
 
@@ -284,7 +284,7 @@ app.use(mw1, [mw2, r1, r2], subApp)
 
 </table>
 
-Following are some examples of using the [express.static](/guide/using-middleware.html#middleware.built-in)
+Following are some examples of using the [express.static](/{{page.lang}}/guide/using-middleware.html#middleware.built-in)
 middleware in an Express app.
 
 Serve static content for the app from the "public" directory in the application directory:

_includes/api/en/4x/res-render.md

@@ -8,7 +8,7 @@ Optional parameters:
 
 The `view` argument is a string that is the file path of the view file to render. This can be an absolute path, or a path relative to the `views` setting. If the path does not contain a file extension, then the `view engine` setting determines the file extension. If the path does contain a file extension, then Express will load the module for the specified template engine (via `require()`) and render it using the loaded module's `__express` function.
 
-For more information, see [Using template engines with Express](/guide/using-template-engines.html).
+For more information, see [Using template engines with Express](/{{page.lang}}/guide/using-template-engines.html).
 
 **NOTE:** The `view` argument performs file system operations like reading a file from disk and evaluating Node.js modules, and as so for security reasons should not contain input from the end-user.