[chuck-users] NullPointerException

[eduard aylon]

> There was some time since I used Chuck now, so I may be wrong on this
> one. But I get the feeling that you're not initializing l, right?

That's what I thought at first with the original code but with the  
code below every object contained in l is automatically initialised  
when the list is declared. That's why after Item l[n], print() is  
called all items  and each object's float is printed to stdout.


>
> On 10/06/07, eduard aylon <eduard.aylon at gmail.com> wrote:
>> Hi list,
>>
>> I am trying to make a list of objects where each object has
>> references to other objects, but I am not succeeding and I get a
>> NullPointerException. The piece of code below may represent what I am
>> trying to do.
>>
>> class object
>> {
>>      Std.rand2f(0., 1.) => float f_;
>> }
>>
>> class Item extends object
>> {
>>      2 => int size_;
>>      object item_[size_];
>>
>>      fun void print()
>>      {
>>          for( 0=>int i; i<size_; i++ )
>>              <<< "item [",i,"]", item_[i].f_>>>;
>>      }
>>      <<<"----------------------------------------------">>>;
>>      <<<"calling print from within class definition">>>;
>>      <<<"----------------------------------------------">>>;
>>      print();
>> }
>>
>> 4 => int n;
>> Item l[n];
>>
>> // no problems up until here
>>
>> <<<"----------------------------------------------">>>;
>> <<<"calling print from outside class definition">>>;
>> <<<"----------------------------------------------">>>;
>>
>> for( 0=>int i; i<n; i++ )
>>      l[i].print();   //offending line
>>
>>
>> After execution I get:
>> [chuck](VM): NullPointerException: shred[id=1:test.ck], PC=[37]
>>
>> Excuse me if it's too obvious, but I can't see why it rises the null
>> pointer exception. Any ideas?
>>
>> thanks in advance,
>>
>> eduard
>>
>>
>>
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>>
>
>
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>
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