6.1.1 Macro Functions

Macro Functions: defmacro

A macro is a function that is applied at compile time to replace a piece of code with another. Macro functions in LispE are based on the same principle as pattern programming as demonstrated with defpat functions.

A macro can be divided into different functions, each with its own set of parameters.

Note that the $ operator in macros are used both in the parameter list and as a specific extensor function in the code.

(defmacro name (P1...Pn) code)

A macro is a way to replace code with a more complex definition.

; this macro computes the cube of a number:

(defmacro cube(x) (* x x x))

If we apply this macro in a piece of code:

(cube 10)

cube will be replaced with it definition:

(* 10 10 10)

More Complicated Patterns

The patterns that are available for defpat