jsonparser

A hand written JSON parser in Rust in under 500 lines of code.

This parser reads JSON source from a string and construct a custom JSONValue object in memory.

enum JSONValue {
    Null,
    True,
    False,
    Number(f64),
    String(String),
    Array(Vec<JSONValue>),
    Object(HashMap<String, JSONValue>),
}

All the source code is in the src/main.rs file, including:

• Enum definitions for JSONValue and JSONParseError
• The Parser
• Unit tests
• Quick benchmarks

There is an accompanying blog post for this on my website at https://krishkrish.com/blog/json-parser-in-rust

Usage

To use this parser, you can call the parse function with a JSON source string.

let json = r#"
{
    "name": "John Doe",
    "age": 30,
    "is_student": false,
    "marks": [90, 80, 85],
    "address": {
        "street": "123 Main St",
        "city": "New York"
    }
}

"#;

let json_value = jsonparser::parse(json).unwrap();

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• JSON.org
• serde-rs's json-benchmark