How to ref elements in an array?

[Timo Schmidt]

Hello,

I'm trying to reference the langID of EditionSchema to the array languages in NewsletterSchema. But how to do it? As an example:

There is a NewsletterSchema that contains: {'name':'FirstNewsletter', ['de', 'en']}

Now I want that you can only add a Edition, if the langID is defined in Newsletter.languages.

var NewsletterSchema = new Schema({

name: {type: String, unique: true},

languages: [LangSchema],

});

var LangSchema = new Schema({

identifier: {type: String, lowercase: true, match: IDRegExp, unique: true},

name: String

});

var EditionSchema = new Schema({

newsletter: {type: NewsletterSchema.name, ref: 'Newsletter'},

edition: Number,

langID: {type: LangSchema.identifier, ref: 'Language'}

});

Can you help please me?