When using Angular Schematics, we have been creating files directly in the tree using method tree.create(). This works but is pretty low level and doesn't support great convenience features like --force flag. Besides that generating files by using low level API would not scale when we wanted to create some more sophisticated folder structure.

Luckily there is a great built in solution in form of Angular Schematics templates!

The templating support comes with the ability to pre create real template file which then can be easily parametrized with the options we're passing to our schematics. This is achieved with the help of the following tools...

1. we can use option values directly in the folder ( and file ) name using __myOption__ syntax.
2. we can adjust option value by using helper functions __myOption@myHelper__
3. we can print option value in the template file content using <%= myOption %>
4. similarly we can adjust option value in the template file content using <%= myHelper(myOption) %>
5. file content template syntax is very flexible and allows any kind of javascript expression like <% if(myOption) { some content <% } %>

• every exercise is described step by step inside of the ./hello/src/hello.index.ts file in form of the TODO comments

• don't forget to run npm run build (or run npm run build:watch in other console) in the base ./hello folder so that you compile your Typescript source code into javascript which can be executed using schematics command

• always rememeber to running schematics command with the --dry-run=false flag to actualy perform changes to the file system because by default Angular Schematics run in dry run mode when executing schematics collection using relative path (for example .:<schematic-name> for a local folder, or ../path/to/collection.json:<schematic-name> )

• always remember to use--force flag when running schematics so that you overwrite any previously generated files