dsl for copying values from one object to another

copy.js

function copy( prop ) {
    var receiver, target;
    function bindFrom( obj ) {
        target = obj;
        return copyProp();
    }
    function bindTo( obj ) {
        receiver = obj;
        return copyProp();
    }
    function copyProp() {
        if ( target && receiver ) {
            if ( prop in target ) {
                receiver[prop] = target[prop];
            }
            return receiver;
        }
        return {
            from: bindFrom,
            to: bindTo
        };
    }
    return copyProp();
};

example.js

var result = {id:1, foo: 'bar', baz: null};

var myObj = ['foo', 'baz']
    .map( copy )
    .reduce( function ( obj, copyProp ) {
            return copyProp.from( result ).to( obj ); 
        }, {} ); 
        
//=> {foo: "bar", baz: null}