Please, I need some help with this, to get a better guile hoot understanding.
I'm trying to create a toggle full-screen command.
(define-foreign full-screen-element "document" "fullscreenElement" (ref extern) -> (ref null extern) )
I already have the full-screen and exit full-screen commands. But the command required for testing is giving me some trouble.
The function returns either null or the element, I expected that the null value would be considered as false in scheme but it is not the case. I'm supposed to cast these values ? test for the string "null" ? or is my usage of define-foreign wrong?
Edited: I found out about the external-null? and external-non-null? this work for the mentioned example but I'm still confused about the general approach for define-foreign. Extra care is needed for those functions in scheme code?