This section provides an extended introduction to syntax/parse as a series of worked examples.
8.2.1 Modules and Reusable Syntax Classes
8.2.2 Optional Keyword Arguments
8.2.3 Variants with Uniform Meanings
8.2.4 Variants with Varied Meanings
8.2.4.1 Syntactic Normalization
8.2.4.2 Non-syntax-valued Attributes
8.2.5 More Keyword Arguments
8.2.6 Contracts on Macro Sub-expressions