• The Problems
• The Design
• Tokenizing
• Interpolating
• Whitespace
• Word
• Environment variable reference
• Special variable reference
• Inline expression
• Unsafe expression
• Container expressions
• Lots more TBD
• Escaping
• Caching
• The Implementation
• Variables as list-like objects
• Substitution processing
• API
• Notes
• Doodling
• Incorporate later