cleanup, docs

site/doc/pages/map.txt

@@ -1,6 +1,3 @@
-:title
-map
-
 :sig
 StringList map(StringList items, function<String (String)> f)
 vector<R> map(vector<T> items, function<R (T)> f)
@@ -19,13 +16,11 @@ filter
 :content
 Returns a new list by calling `f` for each item in `items`.
 
-```cpp
-auto upper = map(names, [](String s) { return(to_upper(s)); });
-```
 
 Use `filter()` when you want to keep only matching items, and `map()` when you want to transform each item.
 
-## Related Concepts
 
-- JavaScript / React: `Array.prototype.map()`
-- PHP: `array_map()`
+:example
+StringList names = split("ada,grace", ",");
+StringList upper = map(names, [](String item) { return(to_upper(item)); });
+print(join(upper, ","), "\n");