CJC Module System

Deterministic module resolution, dependency graph construction, and program merging for multi-file CJC programs.

This crate provides the infrastructure for splitting CJC programs across multiple source files. It handles file resolution, import parsing, dependency-graph construction with cycle detection, symbol mangling, visibility enforcement, and final merging of per-module MIR into a single [cjc_mir::MirProgram] suitable for execution.

Design principles

• All internal maps use [BTreeMap] / [BTreeSet] for deterministic iteration order, ensuring reproducible compilation regardless of filesystem enumeration order.
• Symbol mangling uses a module_path::fn_name convention (e.g., math::linalg::solve).
• Cycle detection is performed via DFS with a BTreeSet-backed recursion stack and produces clear error messages.
• The final output is a single merged [cjc_mir::MirProgram] with module-init statements prepended in topological order.

Typical workflow

entry.cjc ─► build_module_graph() ─► ModuleGraph
                                        │
                     merge_programs() ◄─┘
                          │
                     MirProgram (ready for cjc-mir-exec)