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JSON

lib/json/Json.mt provides type-driven JSON serialization and deserialization. Unlike key-value JSON libraries, mType's Json works directly against your classes — you serialize an object and deserialize back into a typed instance.

Json is a static facade — every method is called with Json::method(...).

Serialize​

import * from "lib/json/Json.mt";

class User {
    public string name;
    public int    age;
    public constructor(string name, int age) {
        this.name = name;
        this.age = age;
    }
}

User u = new User("Alice", 30);
string raw = Json::serialize(u);
print(raw);   // {"name":"Alice","age":30}

For pretty-printed output:

string pretty  = Json::stringify(u);  // multi-line, indented
string compact = Json::compact(u);    // single-line
string fmtted  = Json::format(raw);   // re-format an existing string

To control whether static fields appear and to choose pretty/compact in one call:

string out = Json::serializeWithOptions(u, /*includeStatic=*/false, /*prettyPrint=*/true);

Deserialize​

The deserializer needs to know which class to construct. Pass the class name as a string:

string raw = "{\"name\":\"Alice\",\"age\":30}";
User u = Json::deserializeAs(raw, "User");
print(u.name);   // Alice
print(u.age);    // 30

If the receiver type is fully inferable at the call site (rare in practice — usually you'll need deserializeAs):

User u = Json::<User>deserialize(raw);

File I/O​

// Read JSON from disk and deserialize as User.
User u = Json::readFromFile("/path/to/user.json", "User");

// Serialize and write to disk.
Json::writeToFile("/path/to/out.json", u);

// Pretty-print and include static fields.
Json::writeToFileWithOptions("/path/out-pretty.json", u, /*includeStatic=*/true, /*pretty=*/true);

API Summary​

MethodReturns
Json::serialize<T>(T obj)string (compact)
Json::serializeWithOptions<T>(T obj, bool includeStatic, bool prettyPrint)string
Json::stringify<T>(T obj)string (pretty)
Json::compact<T>(T obj)string (single-line)
Json::deserialize<T>(string json)T (uses inferred type)
Json::deserializeAs<T>(string json, string className)T
Json::format(string json)string (re-formatted)
Json::readFromFile<T>(string path, string className)T
Json::writeToFile<T>(string path, T obj)void
Json::writeToFileWithOptions<T>(string path, T obj, bool includeStatic, bool prettyPrint)void

See Also​