Macro json

json!() { /* proc-macro */ }

Lints and properly formats a JSON object, array, or value.

This proc-macro supports:

• all literals (integers, floats, &str)
• String
• any expression that evaluates to a impl Display

If you are looking for custom serialization traits, macros, and functions, use serde_json and serde instead.

Examples:

Serializing an object:

// You have to have the `ToJson` trait restriction since
// the json! macro uses ToJson. Should a struct not
// implement ToJson, you can use the derive macro.
fn obj<J: json_proc::ToJson>(input: J) -> String {
    json!({
        "hello": "world!",
        thisDidntNeedQuotes: "wow!",
        // this will essentially become `format!("{}", input.to_json_string())`
        anExpression: input
    })
}

Serializing an array:

fn arr<J: json_proc::ToJson>(input: J) -> String {
    json!([
        input,
        (2 + 11) as f32 / 2.0,
        "literal"
    ])
}