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Crate oak_yaml

Crate oak_yaml 

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§🛠️ YAML Parser Developer Guide

Yaml support for the Oak language framework.

This guide is designed to help you quickly get started with developing and integrating oak-yaml.

§🚦 Quick Start

Add the dependency to your Cargo.toml:

[dependencies]
oak-yaml = { path = "..." }

§Basic Parsing Example

The following is a standard workflow for parsing a YAML document:

use oak_yaml::{YamlParser, SourceText, YamlLanguage};

fn main() {
    // 1. Prepare source code
    let code = r#"
        version: "3.8"
        services:
          web:
            image: "nginx:latest"
            ports:
              - "80:80"
          db:
            image: "postgres:13"
            environment:
              POSTGRES_PASSWORD: example
    "#;
    let source = SourceText::new(code);

    // 2. Initialize parser
    let config = YamlLanguage::new();
    let parser = YamlParser::new(&config);

    // 3. Execute parsing
    let result = parser.parse(&source);

    // 4. Handle results
    if result.is_success() {
        println!("Parsing successful! AST node count: {}", result.node_count());
    } else {
        eprintln!("Errors found during parsing.");
    }
}

§🔍 Core API Usage

§1. Syntax Tree Traversal

After a successful parse, you can use the built-in visitor pattern or manually traverse the Green/Red Tree to extract YAML mappings, sequences, scalars, and handle anchors/aliases.

§2. Incremental Parsing

No need to re-parse massive YAML configuration files when small changes occur:

// Assuming you have an old parse result 'old_result' and new source text 'new_source'
let new_result = parser.reparse(&new_source, &old_result);

§3. Diagnostics

oak-yaml provides precise error feedback for malformed YAML, such as indentation errors, unmatched brackets, or invalid tag usage:

for diag in result.diagnostics() {
    println!("[{}:{}] {}", diag.line, diag.column, diag.message);
}

§🏗️ Architecture Overview

  • Lexer: Tokenizes YAML source text into a stream of tokens, handling indentation, block vs. flow styles, and various scalar formats.
  • Parser: Syntax analyzer based on the Pratt parsing algorithm to handle YAML’s hierarchical structure and complex value types.
  • AST: A strongly-typed syntax abstraction layer designed for high-performance YAML analysis, formatting, and validation tools.

§🔗 Advanced Resources

  • Full Examples: Check the examples/ folder in the project root.
  • API Documentation: Run cargo doc --open for detailed type definitions.
  • Test Cases: See tests/ for handling of various YAML features and edge cases.

Re-exports§

pub use crate::builder::YamlBuilder;
pub use crate::language::YamlLanguage;
pub use crate::lexer::YamlLexer;
pub use crate::parser::YamlParser;
pub use crate::lsp::highlighter::YamlHighlighter;
pub use crate::language::from_str;
pub use crate::language::to_string;
pub use crate::lsp::YamlLanguageService;
pub use crate::lsp::formatter::YamlFormatter;
pub use crate::mcp::serve_yaml_mcp;
pub use lexer::token_type::YamlTokenType;
pub use parser::element_type::YamlElementType;

Modules§

ast
AST module.
builder
Builder module.
language
Kind definition module. Language configuration module.
lexer
Lexer module.
lsp
LSP module.
mcp
MCP module.
parser
Parser module.

Functions§

parse
Parses a YAML string.