Spec Update: Batch 12 — UI, Routing, Final Cleanup

Date: 2026-04-16 Plans Referenced: Plan 096 (UI widgets), Plan 105 (routing), Plan 106 (navigation) Source Files: ast.rs (WidgetDecl, MsgDecl, ModelBlock, ViewBlock, NavCall stmt variants), token.rs (routes, outlet, link, route, nav keywords) Sections Updated: UI Widgets and Routing (Section 21 — NEW), Appendices (updated)

Old Content

No UI or routing documentation existed.

New Content

UI Widgets and Routing (Section 21)

• Widget declaration: widget Name { model {}, msg {}, view {} }
• Model block: state declarations with defaults
• Msg block: message type declarations
• View block: widget tree using AURA components
• emit for sending messages
• Routing: routes { route(path, view) }
• Navigation: nav(path), link(text, to), outlet()

Appendices Updated

• Appendix A: Precedence table expanded from 9 to 11 levels
• Appendix B: Keywords expanded from 24 to 56
• Appendix C: NEW — Expression types list (55 variants from ast.rs)
• Removed old ASCII art grammar (outdated)
• Removed C/Rust implementation code examples (moved to Implementation Comparison, simplified)

Cleanup Applied

• All println() → print() throughout
• Pattern matching arrows: -> → =>
• F-string syntax: {name} → $name and ${expr}
• Removed while keyword references
• Fixed lambda syntax: |a, b| → (a, b) =>
• Fixed old onclick syntax: || println(...) → => print(...)
• Version bumped to 0.2
• TOC restructured from 15 to 24 sections

Notes

• WidgetDecl, MsgDecl, ModelBlock, ViewBlock are AST stmt variants for UI
• NavCall is an expression variant for router navigation
• AURA components (col, row, text, button) are documented in CLAUDE.md, not duplicated in spec
• The Implementation Comparison section was simplified (removed code examples, kept feature table)