Deferrence in JavaScript

scope.js

(function(){
    module.exports = function scope(block) {
        const deferred = [];
        const defer = function(callback, args) {
            deferred.unshift({target: this, callback, args});
        }
        
        try {
            return block(defer);
        } finally {
            deferred.forEach(o => o.callback.apply(o.target, o.args));
        }
    }
})();

usage.js

const scope = require('./scope.js');

const fakeDb = {
    openned: false,
    open: function() { console.log('openned'); this.openned = true; },
    close: function() { console.log('closed'); this.openned = false; },
};
const fakeModel = {
    save: (db) => db.openned ? 'working with DB' : 'failed!',
}
const fakeSocket = {
    connect: () => console.log('connected'),
    disconnect: () => console.log('disconnected'),
}

scope(function(defer){
    fakeDb.open();
    defer(fakeDb.close, []);
    
    fakeSocket.connect();
    defer(fakeSocket.disconnect, []);

    console.log('do something with DB and Socket');
    console.log(fakeModel.save(fakeDb));
});

// openned
// connected
// do something with DB and Socket
// working with DB
// disconnected
// closed

This is made for "synchronous-like" code, ideal to use with async/await but not with callbacks.