How can I define a macro in LISP with N arguments?

Question

I am trying to define a macro in LISP, such as this caller function in a different file

(set_name name My name is Timmy)

(set_name occupation I am a doctor )

(defmacro set_name (list)
   (print list)
)

Macros are supposed to return new code to be executed in place of the macro call, not execute something immediately. — Barmar
– Barmar, Commented Apr 16, 2020 at 20:45
Can you give me an example ? sorry I am new to LISP, I just don't how to pass those arguments into define macro. — Kevin
– Kevin, Commented Apr 16, 2020 at 20:46
Why do you think this should be a macro in the first place, not a function? — Barmar
– Barmar, Commented Apr 16, 2020 at 20:49
The name suggests that it's supposed to set the variable, not print something. What do you really want to do? — Barmar
– Barmar, Commented Apr 16, 2020 at 20:50
I would suggest you read chapter 7 and 8 to get an understanding of CL’s macros gigamonkeys.com/book/macros-standard-control-constructs.html — Martin Buchmann
– Martin Buchmann, Commented Apr 16, 2020 at 20:51

Barmar · Accepted Answer · 2020-04-16 20:53:17Z

6

Just like in ordinary functions, use &rest to collect all the remaining arguments into a list.

(defmacro set_name (name &rest list) 
  `(setq ,name ',list))
(set_name occupation I am a doctor)
(print occupation)

This will print (I AM A DOCTOR)

You need to quote ,list in the expansion so it won't try to evaluate all the symbols as variables.

answered Apr 16, 2020 at 20:53

Barmar

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