sim-codec-python

Bounded, lossless Python 3.14.6 source tokenization, concrete syntax trees, and the loadable general-purpose codec/python expression codec. The codec lowers syntax to stable python/* forms, retaining source origins and marking future runtime support independently; it performs no execution and creates no bytecode or control-flow IR.

This is the source frontend for embedded, capability-scoped Python scripting, not a CPython replacement. It never imports or invokes CPython and contains no bytecode, compiler IR, optimizer, project graph, object model, VM, host access, or private language organ. Syntax coverage is intentionally independent from the direct-evaluation and library fidelity published by sim-lib-lang-python.

The frozen production and corpus identities live under grammar/. Parse with parse_module; the returned tree preserves the exact input through SyntaxTree::preserve_source and reports stable located diagnostics on failure. Plain, located, and tree decoding share the codec limits. Canonical encoding re-emits validated Python forms and uses the tagged expression fallback for SIM expressions that Python source cannot otherwise spell.