name: code-review description: Reviews code changes for architectural fitness, extensibility, and alignment with design principles. Use when reviewing code, checking PRs, or validating implementations.

Code Review

Early-stage C++ compiler project. Primary goal: keep architecture clean and extensible.

Review Checklist

1. Architecture and Extensibility

• Does the change fit the intended structure and boundaries?
• If it doesn't fit existing abstractions, should we generalize the design?
• Will this scale as we add more features?

2. No Hacks or Special Cases

• Avoid patch-like solutions with feature-specific workarounds
• No scattered conditional logic ("just for this feature")
• If forcing something in, consider a better abstraction

3. Use Existing Utilities

• Don't reinvent what standard library or codebase already provides
• Use modern C++ when it improves clarity (not for fancy)

4. Error Handling

Check docs/error-handling.md for correct error type usage:

• DiagnosticException only in AST→MIR (with source location)
• InternalError for compiler bugs (MIR→LIR, codegen, unreachable code)
• std::runtime_error for interpreter/SDK runtime failures
• Never use std::unreachable() or DiagnosticException({})

5. Design Principles Alignment

Read docs/design-principles.md and check:

• No Workarounds
• Parameterize, Don't Specialize
• Capture Behavior at the Source
• Unify Before Multiplying
• Follow Established Patterns
• Use Domain Vocabulary
• Comments Explain Why, Not What

6. LIR Design (if touching LIR)

Check that LIR changes follow the correct mental model (see docs/architecture.md):

• Variable access: uses slang's flat symbol model (symbol = unique address, no instance traversal)
• Operations: RISC-V assembly style (register-based, explicit data flow)
• Method calls on complex types: RISC-V function call style (object pointer as this)

Output Format

1. Summary: One sentence on what the change does
2. Architecture: Impact on system structure, potential issues
3. Concerns: Hacky patterns, violations of design principles
4. Suggestions: Better abstractions if needed