next up previous
Contents Next: Mapcar Up: FunctionsLambda Expressions, Previous: Funcall


Apply takes its first argument and applies it as a function to the list of items making up the last. For example:

>(apply '* '(1 2 3 4))
You can imagine this being obtained by constructing the list (* 1 2 3 4) and evaluating the resulting list, although this is not strictly what happens since apply is a function, not a macro. Apply also allows intermediate arguments between the first and the last (see appendix) but the last argument is required to be a list.

Apply can also be used in conjunction with lambda lists. For example:

>(apply '(lambda (x y) (* x y)) '(45 67))
If this does not seem particularly useful to you, think about how it can be used to construct complex programs on the fly.

© Colin Allen & Maneesh Dhagat
May 1999