[Design Pattern: JavaScript Dynamic Proxy] #JavaScript

index.js

/**
 * Dynamic Proxy
 *
 * Wrapping an object with a proxy, and references the previous values.
 * Services is an Object with mixed values, of which is a function ( or even functions ).
 */
const Services = {
    firstname: 'Anita',
    surname: 'Bath',
    gender: 'female',
    salutation: function() {
        return `${Services.firstname} ${Services.surname}`
    }
}
console.log(Services.salutation());
// Anita Bath
const ProxyServices = {
    ...Services // shallow copy
}
console.log('ProxyServices=', JSON.stringify(ProxyServices, null, 4));
// ProxyServices= {
//     "firstname": "Anita",
//     "surname": "Bath",
//     "gender": "female"
// } 
console.log(ProxyServices.salutation());
// Anita Bath
for (const [key,value] of Object.entries(Services)) {
    if ( value instanceof Function ) {
        ProxyServices[key] = (...a) => {
            return `Greetings ${Services.gender === 'male' ? 'Mr' : 'Mrs'} ${Services[key](...a)}`
        }
    }
}
console.log('ProxyServices=', JSON.stringify(ProxyServices, null, 4));
// ProxyServices= {
//     "firstname": "Anita",
//     "surname": "Bath",
//     "gender": "female"
// } 
console.log(ProxyServices.salutation());
// Greetings Mrs Anita Bath