--------------

select
^^^^^^^^

Basis Function Combinator


Use a Boolean value to select one of two items from a sequence.
::

       [A B] false select
    ------------------------
        A


       [A B] true select
    -----------------------
          B

The sequence can contain more than two items but not fewer.
Currently Python semantics are used to evaluate the "truthiness" of the
Boolean value (so empty string, zero, etc. are counted as false, etc.)


Gentzen diagram.


Definition
~~~~~~~~~~

if not basis.


Derivation
~~~~~~~~~~

if not basis.


Source
~~~~~~~~~~

if basis


Discussion
~~~~~~~~~~

Lorem ipsum.


Crosslinks
~~~~~~~~~~

Lorem ipsum.


