[tutorial v1.1_004] Limits the possible values for the variable

"Foo" should not be an option to the "proxy_mode" variable.

Now the "proxy_mode" type is "choice", that means that there is a list of available values that can be selected.

We say that the "proxy_mode" variable is constrained (by choices): this variable accept, in fact, only a list of choices.

firefox/00-proxy.yml

@@ -2,5 +2,13 @@
 ---
 version: 1.1
 
-proxy_mode: No proxy  # Configure Proxy Access to the Internet
+proxy_mode:
+  description: Configure Proxy Access to the Internet
+  choices:
+    - No proxy
+    - Auto-detect proxy settings for this network
+    - Use system proxy settings
+    - Manual proxy configuration
+    - Automatic proxy configuration URL
+  default: No proxy
 ...