Move capitalization rules into section under Naming

notes/style.md

@@ -302,11 +302,7 @@ in plugin scenarios.)
 When in doubt, use **double underscore**.
 
 
-Common language constructs
---------------------------
-
-
-### variables ###
+### Capitalization ###
 
 There are three types of variables recognized in terms of this style.
 The distinction is based on scope:
@@ -324,38 +320,47 @@ The distinction is based on scope:
     be defined in header of the function, that is, before actual code.
     It's also recommended to comment variables here.
 
-For example:
+Functions should be named in `snake_case`.
+
+
+### Example ###
+
+For example, a file named `greet.sh` would be a valid module named `greet`
+if it contained following declarations:
 
     #
-    # My global variable
+    # Name of this planet
     #
-    PLANET_NAME=Earth
+    GREET__PLANET=${GREET__PLANET:-Earth}
 
-    main() {
+    greet() {
+        #
+        # Greet persom named $1
+        #
         local name=$1       # name to greet
         local TimeOfDay     # morning, afternoon or night
         TimeOfDay=$(determine_timeofday)
-        greet "$name"
+        __greet__mkgreet "$name"
     }
 
-    greet() {
+    __greet__mkgreet() {
         #
         # Greet user $1 based on $TimeOfDay
         #
         local name=$1       # name to greet
         case $TimeOfDay in
-            morning)    echo "Good $PLANET_NAME morning, $name!"   ;;
-            afternoon)  echo "Nice $PLANET_NAME afternoon, $name!" ;;
-            night)      echo "Sleep well, $name!"                  ;;
+            morning)    echo "Good $GREET__PLANET morning, $name!"   ;;
+            afternoon)  echo "Nice $GREET__PLANET afternoon, $name!" ;;
+            night)      echo "Sleep well, $name!"                    ;;
         esac
     }
 
-    main "$1"
-
 Notice that while `TimeOfDay` is allowed to slip through and be referenced
-in `greet()`, `name` is purely local to `main()`, and then again to
-`greet()`.  (It's probably not a good idea to mix variables like that,
-the example is ugly, but you get the point.)
+in `__greet__mkgreet()`, `name` is purely local to `greet()`, and then
+`name` happens to be declared again in `__greet__mkgreet()`.
+
+Common language constructs
+--------------------------
 
 
 ### functions ###