Transform MetaAST (M2) back to Python AST (M1).

Implements the reification function ρ_Python that instantiates meta-level representations back into Python-specific AST structures.

Transformation Strategy

The transformation reverses the abstraction performed by ToMeta, using metadata to restore Python-specific information when needed.

M2.1 (Core Layer) → Python AST

• Literals, variables, operators, function calls, conditionals, blocks, early returns

M2.2 (Extended Layer) → Python AST

• Loops: {:loop, :while, ...} → While, {:loop, :for_each, ...} → For
• Lambdas: {:lambda, params, captures, body} → Lambda
• Collection ops: {:collection_op, :map, ...} → ListComp or map() call
• Exception handling: {:exception_handling, ...} → Try

Round-Trip Fidelity

The transformation aims for high fidelity:

• Metadata preserves line numbers and formatting hints
• Default values are provided when metadata is absent