getID.ts

// based on https://stackoverflow.com/questions/1997661/unique-object-identifier-in-javascript
const getID = (function() { // FOR DEBUG ONLY. DO NOT COMMIT!
var id = 0;

return function(o: any): number {
    if ( typeof o.__uniqueid != "undefined" ) {
        return o.__uniqueid;
    }

    Object.defineProperty(o, "__uniqueid", {
        value: ++id,
        enumerable: false,
        // This could go either way, depending on your
        // interpretation of what an "id" is
        writable: false
    });

    return o.__uniqueid;
};
})();