Runtime model

Value stores null, bool, int64, double, string, char, object, function, or class. Numeric representation is preserved (num does not erase int versus float). Object owns a closed field map and points to its Class. Function stores a declaration, lexical closure, and optional receiver. Class stores methods, static fields, and a parent class.

Calls allocate a child Environment containing parameters and (for methods) self. The environment chain implements lexical lookup and closures. Assignment searches the chain but refuses immutable cells. new allocates an instance, initializes declared fields, and invokes init. Objects are owned by the tracing Heap; automatic mark-and-sweep runs at safe statement boundaries, and collectGarbage() provides an explicit diagnostic hook.

The compatibility interpreter remains tree-walking for constructs not yet migrated. The primary compiler path lowers source through HIR and verified MIR into validated register bytecode. No source-to-source translation, host-language eval, or hidden dynamic fallback is used.