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Wave 1 — Contracts, Rollback & Conformance

Wave 1 elevated Aipo beyond conventional interpreters by introducing its defining architectural paradigm: structural data guarantees through signature contracts, atomic rollback invariants, and formal interfaces.

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Achieved Milestones

1. Construction Hooks and Invariants (init and invariant)

• Addition of the init() hook ensures that newly instantiated structures undergo validation and normalization before exposure to consumer code.
• The invariant() block was integrated into stable mutation boundaries. Whenever a struct field is mutated, the runtime rigorously validates declared logical assertions.

2. Transactional Rollback with attempt ... recover

• Implementation of an in-memory mutation journal inside the virtual machine:
  • Entering an attempt block initiates recording of all subsequent object mutations into a rollback journal.
  • If an operational failure (fail) occurs or an invariant() assertion is violated, the journal atomically reverts all modified structs to their pre-attempt state before transferring execution to the recover block.
  • Upon successful block completion, the journal is committed and discarded without lingering memory overhead.

3. Static and Runtime Interface Validation

• Support for formal interfaces and structural conformance:
  • Semantic analysis pre-validates method names, parameter arities, and self receiver compatibility.
  • At runtime, calls dispatched through interfaces perform structural validation, yielding deterministic faults if an incompatible object is provided.

4. Full Support for Local Functions & Module Scopes

• Lexical scope resolution completed with nested local functions and self-referential recursion support via the FillSelfCapture bytecode instruction.
• Transparent and safe access to module-level bindings from impl methods and closures.

5. 100% Green Conformance Gauntlet

• Certified by 20 canonical programs and 19 diagnostic test suites, achieving 100% compliance across all quality gates (fmt, clippy, check, test, doc).