Promotion
ZPL allows arrays to combine with scalars, a convention called “scalar promotion”
Temp := (A@N + A@E + A@W + A@S)/4.0;
Scalars assume shape of the arrays they’re operands with
Another form is “function promotion”
abs(Temp - A)
The (scalar) function is applied to each element of the array
Programmer-written scalar functions can be promoted, too