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JavaScript Backend (aipo-js)

The Aipo JavaScript backend transpiles Aipo source code directly to modern JavaScript (ES2022) with 100% behavioral parity guarantees.

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The Parity Challenge

Many language transpilers targeting JavaScript succumb to loose JS primitive coercion, causing subtle runtime inconsistencies (such as 0 == "" or "5" + 2 == "52").

aipo-js follows a strict strategy:

1. Versioned Runtime Shim: A lightweight pure JavaScript helper library implementing classes and functions that maintain Aipo's strict type semantics, transactional mutation journals, ordered sets/maps, and binary byte manipulation.
2. Clean JS Emission: Lowers control flow constructs to native JS equivalents (functions, classes, try/catch wrapping attempt rollbacks), maintaining high V8 and JavaScriptCore optimization tiers.
3. Source Maps V3: Automatically emits Source Maps V3, enabling native browser devtools and Node.js stack traces to point directly back to the original .aipo source code.

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Differential Conformance Verification

To guarantee that the JavaScript compiler never drifts from the native Rust virtual machine, the project runs continuous differential tests:

• Every program in the conformance test suite is executed on both the native Rust VM and Node.js.
• Any single-character deviation in stdout or mismatched diagnostic code fails the build gate immediately.