using Transform AttributeResolver to get first value of multi-value attribute

[Cantor, Scott]

> So if I understand correctly, this can't be achieved because our Shib-email
> attribute is multi-value?

The mail attribute is formally multi-valued. The SP doesn't know whether any given attribute is multi-valued, it just allows for multiple values in all cases, and there is no mechanism to block that fact from an application.

-- Scott