System Patterns: Grammar::Modelica

Architecture Overview

The repository is organized as a modular Raku grammar package:

• lib/Grammar/Modelica.pm6 as the top-level grammar entry point.

• Feature-specific grammar modules under lib/Grammar/Modelica/ (e.g., expressions, equations, lexical conventions).

• Tests under t/ aligned to grammar areas.

Key Design Patterns in Use

• Composable grammar modules: syntax areas are separated into focused units.

• Spec-driven implementation: grammar rules follow Modelica specification syntax definitions.

• Test-per-domain structure: dedicated test files for major syntax domains.

Emerging / Planned Patterns

• Introduce Action classes to transform parse trees into AST structures.

• Prefer lower-backtracking constructs (token/rule, proto-based dispatch) where appropriate for performance.

• Improve error reporting at grammar/action boundaries for Modelica-specific diagnostics.

Critical Implementation Paths

• Lexical + expression parsing are foundational for most higher-level constructs.

• Class/component/equation parsing composes on top of lexical and expression rules.

• Regression tests should guard parser behavior while modernization proceeds.