updateDeep

map.updateDeep(props)

Assigns each value in props to a property on this map instance named after the corresponding key in props, effectively merging props into the Map. Properties not in props will be set to undefined.

var MyMap = DefineMap.extend({
    list: DefineList,
    name: 'string'
});
var obj = new MyMap({
    list: ['1', '2', '3'],
    name: 'bar',
    foo: {
        bar: 'zed',
        boo: 'goo'
    }
});
obj.updateDeep({
    list: ['first'],
    foo: {
        bar: 'abc'
    }
});

obj.list //-> ['first', '2', '3']
obj.foo //-> { bar: 'abc', boo: undefined }
obj.name //-> 'undefined'