The Complete Rust Programming Reference Guide

Exercises

If you are already finding macros empowering, here are some exercises for you to try so that you can tinker with macros some more:

1. Write a macro that accepts the following language:

        language = HELLO recipient;        recipient = <String>;

For instance, the following strings would be acceptable in this language:

        HELLO world!        HELLO Rustaceans!

Make the macro generate code that outputs a greeting that's directed to the recipient.

2. Write a macro that takes an arbitrary number of elements and outputs an unordered HTML list in a literal string, for instance, html_list!([1, 2]) => <ul><li>1/<li><li>2</li></ul>.