=< evaluates its head against its tail as subject.

=<(a b) is =>(b a), and =<(a [a=5]) is 5.

irregular forms:

arm:core is =<(arm core)

|. makes a trap: a core with only the default arm $ - a computation deferred until you run it.

run it with $ or =< $.

=<($ |.((add 2 2))) is 4.

%: 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.