https://pietschsoft.com/post/2015/09/05/javascript-basics-how-to-create-a-dictionary-with-keyvalue-pairs

// using indexer
var name = dict["FirstName"];

// as property
var name = dict.FirstName;

var dict = {};

var f = function() {
  // do something
};

// setup Function as Value
dict['method'] = f;

// setup Function as Key
dict[f] = 'some value';

// execute Function from Value
dict['method']();

var method = dict.method;
method();

// get value for Key
var val = dict[f];