ason-swift

Swift implementation for ASON, focused on low-allocation encoding/decoding, schema-first data layout, and high-throughput binary pipelines.

中文文档

Highlights

• UTF-8 byte-buffer parser with explicit cursor-based scanning
• SIMD fast-path for special-character detection during string quoting
• No JSON bridge in hot paths (encode/decode/encodeBinary/decodeBinary)
• Schema-first tuple encoding to reduce repeated field-name overhead
• Typed and untyped text modes + pretty format
• Binary codec with typed schema header for direct roundtrip
• Follows the latest ASON spec: schema annotations use @, and complex fields keep the required @{} / @[] structural scaffold
• No standalone map type; dictionary-like data should be modeled as arrays of key-value tuples such as attrs@[{key@str,value@int}]

API

• encode(_:)
• decode(_:)
• encodeBinary(_:)
• decodeBinary(_:)
• encodePrettyTyped(_:)
• encodePretty(_:)
• encodeTyped(_:)

Quick Start

import AsonSwift

let user: AsonValue = .object([
  "id": .int(1),
  "name": .string("Alice"),
  "active": .bool(true)
])

let text = try encode(user)
let typed = try encodeTyped(user)
let parsed = try decode(typed)
let bin = try encodeBinary(user)
let back = try decodeBinary(bin)

let team = try decode("""
{name@str,members@[{id@int,name@str}],attrs@[{key@str,value@str}]}:
  (core, [(1,Alice),(2,Bob)], [(region,apac),(tier,gold)])
""")

Examples

swift run basic
swift run complex
swift run cross_compat
swift run bench -c release

Testing

swift run run_tests

Performance Advantages

• Fewer transient allocations by parsing directly on byte buffers.
• SIMD branch reduces delimiter scanning cost for ASCII-heavy payloads.
• Tuple-style data rows avoid repeated key serialization compared to JSON objects.
• Binary mode avoids text parse overhead and provides stable, compact IO framing.

Test Advantages

• Covers text encode/decode and binary roundtrip.
• Includes escaping, multiline input, comments, and array/object schemas.
• Mirrors the same functional coverage style used by other ASON language ports.
• Suitable as baseline for cross-language compatibility extension tests.

License

MIT. See LICENSE.