How to make destructive function

[ssqq]

some newLISP builtin function is destructive, If user want design destructive function, how to make it?



for every argument passed into user function is value, not reference only if value is stored in a functor.

[TedWalther]

I suggest, use a macro, or else pass in a symbol, you can alter the value that a symbol points to.

[ssqq]

thanks, I think macro may be ok!