!!
=/ a 3 (add a a)

your code runs against a subject — the data it can see.

=/ adds a named value (a face) to it for the lines below.

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.