Examples

The dynamic API and the generated API write the same Frozen bytes. Use the dynamic API when the shape is chosen at runtime. Use a generated struct when a JSON Schema already names the fields.

Dynamic struct

examples/point_roundtrip.rs encodes a Point and decodes it. Run it with cargo run --example point_roundtrip.

use kiln::{decode, encode, Schema, Value};

let schema = Schema::struct_fields([("x", Schema::I32), ("y", Schema::I32)]);
let value = Value::Struct(vec![Value::I32(3), Value::I32(-4)]);
let raw = encode(&schema, &value).expect("encode");
let back = decode(&schema, &raw).expect("decode");
assert_eq!(back, value);

Value::F32 and Value::F64 store IEEE bits. Negative zero is Value::from_f32(-0.0), not a canonicalized 0.0.

One tensor

use kiln::{decode_tensors, encode_tensors, DecodeOpts, Tensor, DTYPE_F32, DEFAULT_CAP};

let payload = [0x00u8, 0x00, 0x80, 0x3f, 0x00, 0x00, 0x00, 0xc0];
let tensor = Tensor::new(DTYPE_F32, &payload).with_shape(&[2]);
let raw = encode_tensors(&[tensor], DEFAULT_CAP).expect("encode");
let dir = decode_tensors(&raw, DecodeOpts::default()).expect("decode");
assert_eq!(dir.tensors[0].data, &payload);

dir.tensors[0].data is a slice of raw. Drop dir before mutating raw.

Generated struct

testdata/schema/point.json describes x, y, and an optional label. After bash scripts/generate.sh, tests/generated/Point.rs has those fields. label is omitted from required, so the wire form is an option tag.

let point = Point { x: 3, y: -4, label: None };
let raw = point.encode().expect("encode");
assert_eq!(point.encoded_size(), raw.len());
let back = Point::decode(&raw).expect("decode");
assert_eq!(back.x, 3);

testdata/schema/message.json nests Meta through $ref. Both structs are emitted into Message.rs. encoded_size is the exact Frozen length, including the length prefixes of strings.