TOML (serde/toml)

TOML (Tom's Obvious, Minimal Language) is the preferred configuration format for Vex projects (vex.json may migrate to vex.toml). The serde/toml module provides a complete parser, encoder, decoder, and a TomlValue AST.

Modules

File	Purpose
parse.vx	TOML text → TomlValue AST parser
value.vx	TomlValue type (Table, Array, String, Integer, Float, Bool, DateTime)
encoder.vx	Struct → TOML string via Serde Serializer contract
decoder.vx	TOML string → Struct via Serde Deserializer contract

Parsing into AST

import { parse } from "serde/toml";

let input = "[server]\nhost = \"0.0.0.0\"\nport = 8080\n\n[database]\nurl = \"postgres://localhost/app\"";

let toml = parse(input);
// toml is a TomlValue.Table with nested tables

Encoding (Struct → TOML)

import { encode } from "serde/toml";

struct ServerConfig {
    host: string
    port: i32
    debug: bool
}

let cfg = ServerConfig { host: "localhost", port: 3000, debug: false };
let toml_str = encode<ServerConfig>(&cfg);
// → host = "localhost"\nport = 3000\ndebug = false

Decoding (TOML → Struct)

import { decode } from "serde/toml";

let input = "host = \"0.0.0.0\"\nport = 9090\ndebug = true";
let! cfg = ServerConfig { };
decode<ServerConfig>(input, &cfg);
println("Listening on {cfg.host}:{cfg.port}");

Performance

TOML decode benchmarks reach ~1,029,232 ops/s due to the internal AST-based parsing that avoids re-scanning and uses span-sliced string extraction throughout.