Module json 

Canonical-JSON renderer for the Parquet attributes_json column.

Per 10-data-model.md § 4 and 20-parquet-exporter.md § 3.3:

• keys sorted alphabetically at every object level;
• numbers rendered with ryu (shortest exact f64 representation);
• HCL null/bool/string/list/map → JSON equivalents;
• Expression::Unresolved → {"__unresolved__": "<source>", "__kind__": "Var|Local|..."};
• Expression::FuncCall → {"__unresolved_func__": "<name>", "args": [...]};
• the renderer never panics: any non-finite f64 (NaN, ±∞) is rendered as JSON null to keep the artefact strict-JSON valid.

The renderer is deterministic: same input → byte-identical output.

Functions

attribute_map_to_string

Convenience: produce the canonical JSON of an AttributeMap as a freshly-allocated String.

render_attribute_map

Render an AttributeMap as canonical JSON object into out.