I have a sub which if all goes well returns an array but if a error is encounted returns undef. I belived this to be good style and know that many built in functions do this.

However I encounted some problems with this and could do with your opinions on where I'm going wrong. The following code will demonstrate whats been happening.

&mysub2(mysub1);
sub mysub1{
    #normally returns an array.
    
    #on error 
    return undef;
}
sub mysub2{
    my @array = @_;
    unless(@array){
        print "Array is not defined" #Expected out come
    }else{
        print "Exists";
    }
}

[download]
I expected "Array is not defined" but get "Exists". I've tried using defined but -w told me that this is depricated for arrays. So why am I getting this unexpected result?

In reply to sub returning undef by Scarborough

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