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Re: !null values in arrays [message #74042 is a reply to message #74040]

Thu, 16 December 2010 07:14

Paul Van Delst[1]
Messages: 1157
Registered: April 2002

Senior Member

Hello,

Axel M wrote:
> Hi Gray,
>
> I see your point and agree to some extent. But I would also see the
> opposite arguments: what should then be the result of 3 * !NULL or
> 3 / !NULL ? Do you propose that !NULL is handled as a 0? This might
> often lead to more confusion, and for indexing purposes it is
> definitely not a 0.

In IDL, storing a null in an otherwise homogeneous array makes said array a list. Why not use a list? The OP could still
call it an array.... :o)

Purely for perspective into the issue, ruby handles operations with null values thusly:

irb(main):001:0> 3 + nil
TypeError: nil can't be coerced into Fixnum
from (irb):1:in `+'
from (irb):1

and python similarly:

>>> 3 + None
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: unsupported operand type(s) for +: 'int' and 'NoneType'

cheers,

paulv

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[Message index]

		Re: !null values in arrays By: penteado on Thu, 16 December 2010 07:39
		Re: !null values in arrays By: Paul Van Delst[1] on Thu, 16 December 2010 07:14
		Re: !null values in arrays By: Axel Martínez on Thu, 16 December 2010 03:30
		Re: !null values in arrays By: David Fanning on Wed, 15 December 2010 10:20

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