Question: ```
List<Person> person = A.ListOf<Person>(20);

```

I'm performing mocking. For that i'm using Genfu nuget library to generate fake data for various properties. It does populate fake data but generates some duplicate data which I don't want. 

I want the Id & Email property to be unique. How can this be achieved ?

Answer: 
Got the solution for it. This will refrain it from providing duplicate values for Id property.

```
var i = 0;
person = A.ListOf<Person>(20);
person.ForEach(x =>
{
    i++;
    x.Id = i;
});

```
I am afraid that's not currently possible. 

See the tracking [issue](https://github.com/MisterJames/GenFu/issues/50) for more details. 

You can play around with the fill to enforce unique on your own for certain members. 

```
    A.Configure<Person>()
            .Fill(x => x.Id, x => myOwnWayToEnforceUniqueness());

```

Of course that kills the point of using a mocking library but it can be helpful if unique does not matter for the rest of the fields.