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A Question About Indexing With Nulls

New Contributor III
Nulls under the cover must be treated as a "special value" in that you cannot do arithmetic on them, but interestingly enough you can do comparisons--where 0N is treated as the smallest number even less than -0W (0N < -0W).  Is this by definition or based on the internal representations of 0N and -0W and a straight "less than" operation is being done under the covers?  I know 0N and 0n are represented by NaN, but I'm not sure if the processor is capable of doing arithmetic/comparisons with NaNs.

This leads to my next question which is indexing with nulls.  I know a null is always returned when you index into a list with a null, but again does the interpreter special case the null or view it as a really small number, under-indexing the list, and returning a null?

I'm assuming since you can do arithmetic on infinities, that indexing with 0W and -0W is equivalent to indexing with a very large and very small number and thus nulls are returned in this case.

Thanks for any insight.

New Contributor II
New Contributor II
indexing outside of domain results in null