newlispfanclub.alh.net

Posted: **Wed Jul 27, 2016 12:32 pm**

if you use true? as checking function for list, be attention to: blank list -> '(), would not match it.


> (true? '())
nil

If you often use it, advise you use :

> (define (bool x) (if (nil? x) nil true))
> (for-all bool '(1 2 3 4 () 6))

Posted: **Fri Aug 05, 2016 12:26 pm**

ssqq wrote:if you use true? as checking function for list, be attention to: blank list -> '(), would not match it.
Code: Select all
> (true? '())
nil

`true?` works as advertised.

http://www.newlisp.org/downloads/newlis ... html#truep

I don't see any problem with it, and so I don't consider it "dangerous".

dangrous true?