!!
%- dec %+ add 3 4

a one-argument call whose argument is itself a call, all the way tall.

glossary

%- calls a gate on one argument (or one cell of arguments).

%-(dec 8) is 7.

irregular forms:

(gate arg) is %-(gate arg)

dec is decrement: one less than an atom.

(dec 8) is 7.

%+ calls a gate that takes two arguments.

%+(add 2 3) is 5.

irregular forms:

(gate a b) is %+(gate a b)

add sums two atoms.

(add 2 3) is 5.