Blurb::
Name the interface block; helpful when there are multiple
Description::
The optional ``id_interface`` keyword accepts a string that uniquely
identifies this interface block.  A model can then use this interface
by specifying the same string in its ``interface_pointer``
specification.

*Default Behavior*

If the ``id_interface`` specification is omitted, a particular
interface specification will be used by a model only if that model
does not include an ``interface_pointer`` and the interface block was
the last (or only) one parsed.

*Usage Tips*

- It is a best practice to always use explicit interface IDs and  pointers to avoid confusion.


- If only one interface block exists, then ``id_interface`` can be  safely omitted from the interface block (and ``interface_pointer``  omitted from the model specification(s)), since there is no  ambiguity.
Topics::
block_identifier
Examples::
For example, a model specification including

.. code-block::

    model
      interface_pointer = 'I1'

will link to an interface with

.. code-block::

    id_interface = 'I1'


Theory::

Faq::

See_Also::
