1. What is a macro
  2. todo!
  3. Declarative macros
  4. Hello World macro
  5. Macro with parameter to say hello
  6. Macro with optional parameter to say hello
  7. Macro with many parameters to say hello
  8. Macro to create a HashMap to be a counter
  9. HTML to string macro
  10. Num traits
  11. Procedural macros
  12. Macro accepting a single string
  13. Accept list of values as a plain string in a macro
  14. Compile random number in the code using macro
  15. SQLx - compile-time SQL queries
  16. Macro ok! to replace unwrap
  17. Error logging