neco-kdl

日本語

Zero-dependency KDL v2 parser and serializer. Suitable for configuration files and DSL parsing.

Features

• Full KDL v2 specification parsing
  • Multiline strings, raw strings, escline
  • Type annotations: (type)node
  • Slashdash comments (/-), block comments (/* ... */), nested comments
  • #true / #false / #null / #inf / #-inf / #nan keywords
  • Hex, octal, binary literals with underscore separators
  • Version marker (/- kdl-version 2)
• Serialization via serialize() and Display impl (roundtrip-safe)
• Normalized output (matches official test suite expected_kdl)
• Format-agnostic Value conversion (Value <-> KdlDocument)
• Zero external dependencies
• Passes the full official test suite

Usage

[dependencies]
neco-kdl = "0.2"

use neco_kdl::{parse, serialize, normalize};

fn main() {
    let src = r#"
        node "hello" key=#true {
            child 42
        }
    "#;

    let doc = parse(src).unwrap();

    // Iterate over nodes
    for node in doc.nodes() {
        println!("{}: {} entries", node.name(), node.entries().len());
    }

    // Serialize back to KDL
    let output = serialize(&doc);
    print!("{}", output);

    // Convert to normalized form
    let normalized = normalize(&doc);
    print!("{}", normalized);
}

API

parse

pub fn parse(input: &str) -> Result<KdlDocument, KdlError>

Parses a KDL v2 document and returns a KdlDocument.

serialize

pub fn serialize(doc: &KdlDocument) -> String

Converts a KdlDocument back to KDL text. All types (KdlDocument, KdlNode, KdlEntry, KdlValue) also implement Display.

normalize

pub fn normalize(doc: &KdlDocument) -> String

Converts a KdlDocument to its normalized string form. Normalization rules:

• Strips comments
• Sorts properties by key in alphabetical order
• Deduplicates properties (last occurrence wins)
• Converts all strings to quoted strings
• Unquotes strings that are valid identifiers
• Indents with 4 spaces
• Converts numbers to decimal, strips underscores
• Adds trailing newline

value_to_kdl_document / kdl_document_to_value

pub fn value_to_kdl_document(value: &Value) -> Result<KdlDocument, KdlError>
pub fn kdl_document_to_value(doc: &KdlDocument) -> Result<Value, KdlError>

Converts between KdlDocument and a format-agnostic Value enum. Value serves as an intermediate representation for bridging KDL with other formats (JSON, CBOR, etc.) without external dependencies.

Types

License

MIT