Array length & allocation question

[Bruno Medeiros]

Oskar Linde wrote:
> 
> Like this:
> 
> void foo(char[] arr) {
>     if (!arr)
>         writefln("Uninitialized array passed");
>     else if (arr.length == 0)
>         writefln("Zero length array received");
> }
> 
> /Oskar

This is not safe to do. Currently in D null arrays and zero-length 
arrays are conceptually the same. It just so happens that sometimes the 
arr.ptr is null and sometimes not, depending on the previous operations.
The "A 'dup'ed empty string is now a null string." is an example of why 
that is not safe. I thought you knew this already? This is nothing new.

BTW, I do find it (at first sight at least) unnatural that a null array 
is the same as a zero-length arrays. It doesn't seem conceptually 
right/consistent.



-- 
Bruno Medeiros - CS/E student
http://www.prowiki.org/wiki4d/wiki.cgi?BrunoMedeiros#D