This chapter needs splitting:

• intro: macro_rules is behind a feature gate + simple example (no arguments)
• arguments and designators: $foo:expr
• variable number of arguments: I would like to use @vks range! example here
• commas are not needed to separate the arguments: do!($this and $that)
• + and * expansion
• stay DRY: generating test suite / trait implementations using macros

We also want to cover:

• How to link "macro" crates #[phase(plugin)]