I'm stuck. Why does the first example work but not the second? Thanks!

(setf v1 '((-w h a4 d4)
           (h f4 e4 d4 q a4 g4)
           (q f4 g4 e a4 bb4 c5 a4 q bb4 h a4 q g4)
           (h a4 bb4 w a4)))

First example:

(loop for n from 1 to 4
      collect
        (get-events '(1 2 (2..4)) v1)) ;; "works"

Second example:

(loop for n from 1 to 4
      collect
        (get-events '(1 n (2..4)) v1)) ;; doesn't work, why?

This is the error message:

Error: In 1- of (n) arguments should be of type number.
  1 (continue) Return a value to use.
  2 Supply a new argument.
  3 (abort) Return to top loop level 0.

 

(loop for n from 1 to 4
      collect
        (get-events (list 1 n '(2..4)) v1))

 

Jesper

Thanks Jesper, works like a charm! 🤩

;;asign 3 variables a, b, and c to 1, 2 and 3

(setf a 1 b 2 c 3)

(list a b c)
=>(1 2 3)

'(a b c)
=>(a b c)
 

Jesper

Also possible:

 

(loop for n from 1 to 4
      collect
        (get-events `(1 ,n (2..4)) v1))

 

Yes, but macros and backquote are a bit harder to understand.

 

Jesper

 

 

29 minutes ago, jesele said:

Yes, but macros and backquote are a bit harder to understand.

 

Jesper

 

 

indeed, you are right. I agree for macros but this simple example of use of backquotes list and comma to evaluate is not too difficult I think and very elegant.

Yes, I like them.