=/ a 4
(add a (mul a a))
a face can be used as many times in a line as you like.
glossary
=/ pins a named value (a face) into the subject for the lines below it.
name=value optionally declares the type.
=/(a 3 (add a a)) is 6.
%: calls a gate with several arguments, gathering them into one sample.
%:(add 2 3) is 5.
irregular forms:
(gate a b c) is %:(gate a b c)
add sums two atoms.
(add 2 3) is 5.
mul multiplies two atoms.
(mul 3 4) is 12.