urbit/try/bin/toy.hoon

!:             ::  To write a trivial Hoon program
|=  *          ::
|=  [x=@ ~]    ::  For educational purposes only
:_  ~  :_  ~   ::
:-  %$         ::  Preserve this mysterious boilerplate square
!>             ::
:::::::::::::::::  Produce a value below
~&  %foo
(add 2 x)