Apply suggestions:

* Forbid generics without a path (so "<p>" is forbidden).
 * Change `handleSingleArg` so that it takes `results_others`, `results_in_args` and `results_returned` as arguments instead of using the "global" variables.
 * Change `createQueryElement` so that it returns the newly created element instead of taking `elems` as argument.
 * Improve documentation

src/test/rustdoc-js-std/parser-generics.js

@@ -1,29 +1,6 @@
-const QUERY = ['<P>', 'A<B<C<D>,  E>', 'p<> u8'];
+const QUERY = ['A<B<C<D>,  E>', 'p<> u8'];
 
 const PARSED = [
-    {
-        elems: [{
-            name: "",
-            fullPath: [""],
-            pathWithoutLast: [],
-            pathLast: "",
-            generics: [
-                {
-                    name: "p",
-                    fullPath: ["p"],
-                    pathWithoutLast: [],
-                    pathLast: "p",
-                    generics: [],
-                },
-            ],
-        }],
-        foundElems: 1,
-        original: "<P>",
-        returned: [],
-        typeFilter: -1,
-        userQuery: "<p>",
-        error: null,
-    },
     {
         elems: [],
         foundElems: 0,