Re: [chuck-users] .cap() for multi-dimensional arrays

3 Oct 2007

      It makes sense when you think of multi dimensional arrays as just  
arrays of arrays.  Additionally each sub-array need not be of equal  
length.  Try running this code for example:

int a[4][5];

<<< "here", "" >>>;

for( 0 => int i; i < a.cap(); i++ )
     <<< a[i].cap(), "" >>>;

<<< "there", "" >>>;

int b[4] @=> a[1];

for( 0 => int i; i < a.cap(); i++ )
     <<< a[i].cap(), "" >>>;

In this case if you relied on a[0].cap() specifying the length for  
each sub-array you could get yourself a NullPointerException trying  
to access a[0][4].

spencer

On Oct 1, 2007, at 2:49 AM, Kassen wrote:
...
On 10/1/07, Martin Ahnelöv  wrote:
Eh? What are you... Hm... Okay, I can see your point now. You're  
right.
Since we are dealing with arrays, every array inside foo[i] will be of
equal length; it's not like we are dealing with lists where every slot
is just a reference to another object.
Good thinking there.
It gets very useful. Suppose we have two positive integers X and Y  
in a file so that;
-----------------------------------------------------------
array[X][Y] @=> Foo.foo_array;
Foo foo;
public class Foo
  {
static int foo_array[][];
fun void bar(int blah)
    {
    ................
    }
  }
----------------------------------------------------------
Because Foo is a public class holding a static array the array  
needs to be instantiated outside of the class or there will be  
errors. Now if Foo.bar() does something to that array it becomes  
quite important to determine what it's dimensions are, however,  
both X and Y are outside of Foo's namespace and it's quite possible  
that there will be many instances of Foo that are in different  
files altogether which won't have X or Y.
At that point the .cap()'s of multi-dimensional arrays become very  
interesting so I thought I'd share because it's not in the manual  
nor does my workaround look very nice. Also; this took a while to  
figure out and it makes no sense for others to spend that time too.
Yours,
Kas.
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Re: [chuck-users] .cap() for multi-dimensional arrays

Spencer Salazar