Wrong error messages when invoking macro

[jcubic]

Example code:

(define-syntax foo
  (syntax-rules ()
    ((_ var1 ... var2)
     (begin
       (print var1)
       ...
       (print var2)))))

(foo)

the macro foo expects at least 1 argument. But it throws an error:

TypeError: code.length is not a function in macro: (() ((_ body1 ... body2) (begin (print body1) ... (print body2))))
    at traverse (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:3573:41)
    at traverse (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:3745:17)
    at extract_patterns (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:3761:9)
    at Environment.<anonymous> (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:7969:36)
    at Syntax.invoke (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:3474:24)
    at evaluate_syntax (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:9833:23)
    at evaluate (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:9979:22)
    at exec_lambda (file:///home/kuba/projects/jcubic/scheme/lips/src/lips.js:10032:27)
    at async run (file:///home/kuba/projects/jcubic/scheme/lips/bin/lips.js:69:16)
[1]: (foo)