Create models with enforced data types that can reference other models as data types themselves

JSModel.js

function Model(name, OBJ) {
    function model(obj) {
        var PUBLIC = this;
        var PRIVATE = {};
        PUBLIC.MODEL_TYPE = name;

        for (let key in obj) {
            let value = obj[key];

            // Ensure property is set correctly
            if (key.match(/\w+_.+/) == null) {
                throw new Error("Property does not contain both data type and property name: TYPE_NAME");
            }
            // Extract name and type from property
            let type = key.substring(0, key.indexOf("_"));
            let name = key.substring(key.indexOf("_") + 1, key.length);
            
            //  Map value to the private space
            PRIVATE["__" + name] = value;

            // Define the setter and getter
            Object.defineProperty(PUBLIC, name, {
                set: function (val) {
                    // Support null
                    if (val === null || val === undefined) {
                        PRIVATE["__" + name] = null;
                    }
                    // Enforce model types
                    if (val.MODEL_TYPE) {
                        if (val.MODEL_TYPE == type) {
                            PRIVATE["__" + name] = val;
                        } else {
                            throw new Error(name + " cannot be set as a " + (val.MODEL_TYPE) + " model because it is defined as a '" + type + "'");
                        }
                    } else { // Enforce data types
                        if (typeof val == type) {
                            PRIVATE["__" + name] = val;
                        } else {
                            throw new Error(name + " cannot be set to a " + (typeof val) + " because it is defined as a '" + type + "'");
                        }
                    }

                },
                get: function () {
                    return PRIVATE["__" + name];
                }
            });
        }
        return PUBLIC;
    }
    
    return function (obj) {
        var m = new model(OBJ); // set default values
        for (var k in obj) { // load specified values
            if (m[k] !== undefined) {
                m[k] = obj[k];
            } else {
                throw new Error(k + " is not specified as a property in the " + name + " model");
            }
        }
        return m;
    }
}


// property types are encforced
var test = new Model("t", {
    string_MyName: "seth", // set a property type like so
    number_num: 10 
})
// models can be used as types
var test2 = new Model("t2", {
    test_modelProperty: new test()
})