Re: equal? and primitive arrays

[Per Bothner <per at bothner dot com>]

On 10/07/2011 10:38 PM, Jamison Hope wrote:
> On Oct 7, 2011, at 10:33 PM, Jamison Hope wrote:
>
> > I'll tackle the primitive arrays for now and think about how to handle
> > cycles as a separate patch.
>
> Here's what I came up with. I get the expected successes and failures
> for statements like (test-equal (byte[]) (byte[])) or
> (test-equal (byte[] 1 2) (long[] 1 2)).

In arrayEquals we could perhaps simplify/optimize slightly:

  String tname1 = arg1.getClass().getName();
  String tname2 = arg2.getClass().getName();
  // int[].class.getName() returns "[I" etc
  if (tname1.length() == 2 && tname2.equals(tname1)) { // matching 
primitive types
     switch (tname1.charAt(1)) {
          case 'Z':  return Arrays.equals((boolean[]) arg1, (boolean[]) 
arg2);
          ... etc ...
  }

> I'm a little uncertain what the correct behavior should be for edge
> cases like comparing a String[] to an FString[] in which each pair
> of elements are equal?. For now, that will return #f because the
> array component types are not equal (in the Java sense).

I think the result should be #f because the types are different.
--
	--Per Bothner
per@bothner.com   http://per.bothner.com/