The json module

JSON: parse text into a JsonValue, look values up and change them, and write them back as compact or indented text.

Bring it in with import json. Parsing follows RFC 8259 strictly, and accepts JSONC (comments and trailing commas) on request. Objects keep their keys in the order they were written, so a document round-trips unchanged. encode and decode convert structs to JSON text and back.

• JsonValue: JsonValue
• Parsing: parse, JsonError
• Documents with comments: parse_document, JsonDocument
• Struct conversion: encode, decode, to_json, from_json, UnknownKeys, with the attributes of the serialize module

Example

import json;

main(): int {
    var parsed = json.parse("{\"name\": \"pepper\", \"port\": 8080}");
    if (parsed.is_err()) {
        print(parsed.error().to_string());
        return 1;
    }
    var root = parsed.value();
    assert(root["name"].as_string().value() == "pepper", "a string");
    assert(root["port"].as_int().value_or(80) == 8080, "a number");
    root["debug"] = json.JsonValue.Bool(true);
    assert(root.to_string() == "{\"name\":\"pepper\",\"port\":8080,\"debug\":true}", "compact");
    return 0;
}

Source: runtime/json/module.pep