Arg package:Agda
Named argument, like x in {x = v}
Describes whether an option takes an argument or not, and if so how
the argument is injected into a value of type a.
A function argument can be hidden and/or irrelevant.
Names in binders and arguments.
Usage status of function arguments in treeless code.
Call matrix indices = function argument indices.
Machine integer
Int is sufficient, since we cannot index more
arguments than we have addresses on our machine.
Sometimes we want a different kind of binder/pi-type, without it
supporting any of the Modality interface.