ProxyMap. Maybe what objects should have been?

ProxyMap.js

"use strict";

(function(global){

    var handler = new Proxy({
        get: function(target, name){
            return target.get(name);
        },
        set: function(target, name, value){
            target.set(name, value);
            return true;
        },
        delete: function(target, name){
            return target.delete(name)
        },
        has: function(target, name){
            return target.has(name)
        }
    },
    /*throwingMetaHandler*/ {
        get: function(target, trap){
            var op = target[trap];
            
            if(typeof op !== 'function')
                throw new Error('The trap '+trap+' cannot be used')
            else
                return target[trap];
        }
    });

    global.ProxyMap = function ProxyMap(){
        return new Proxy(new Map(), handler);
    }

})(this);

So basically, it's a wrapper around maps to make them look like objects. It's just syntactic sugar.
The interesting part is that it's an object with all the ES5 property descriptor details removed.

The meta-handler trick is here because I'm lazy to make all unwritten traps throw :-)

Suggestions:

• There seems to be a closing parenthesis missing (line 29, instead of the curly brace.

• Show a few examples of ProxyMap in use.

• I’d set it up like this:

  var ProxyMap = function () {
      ...
      return function () { ... };
  }();
  

"use strict"; outside of IIFE? :(

Thanks for your comments. Weird at didn't get the notifications at the time...
@rwldrn what's the problem with the "use strict" outside the IIFE?