Re: Thinking about MINUS
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Tue, 09 Jan 2007 20:53:28 GMT
Message-ID: <chToh.42809$cz.626896_at_ursa-nb00s0.nbnet.nb.ca>
>>Gene Wirchenko wrote:
>>
>>
>>>Bob Badour <bbadour_at_pei.sympatico.ca> wrote:
>>>
>>>[snip]
>>>
>>>
>>>>Unless we make one up, we have no + operation that operates on numbers
>>>>and strings. Similarly, we have no < comparison that operates on numbers
>>>>and strings. However, the equality comparison operates on any two values
>>>>(unless we go out of our way to redefine it otherwise.)
>>>>
>>>>Semantically, it makes no sense to say "This orange is less than that
>>>
>>>
>>>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>>
>>>
>>>>apple"; however, it makes perfect sense to say "This orange is not that
>>>
>>> ^^^^^^
>>> I would substitute 'Similarly, it makes no sense to say "This
>>>orange is less than that apple", unless we have defined a less than
>>>operator.' For example, the comparison might be of weight or of cost.
>>
>>But then the question becomes: "Is this weight less than that weight?"
>>and "Is this cost less than that cost?" which are completely different
>>questions.
Date: Tue, 09 Jan 2007 20:53:28 GMT
Message-ID: <chToh.42809$cz.626896_at_ursa-nb00s0.nbnet.nb.ca>
Gene Wirchenko wrote:
> Bob Badour <bbadour_at_pei.sympatico.ca> wrote: > >
>>Gene Wirchenko wrote:
>>
>>
>>>Bob Badour <bbadour_at_pei.sympatico.ca> wrote:
>>>
>>>[snip]
>>>
>>>
>>>>Unless we make one up, we have no + operation that operates on numbers
>>>>and strings. Similarly, we have no < comparison that operates on numbers
>>>>and strings. However, the equality comparison operates on any two values
>>>>(unless we go out of our way to redefine it otherwise.)
>>>>
>>>>Semantically, it makes no sense to say "This orange is less than that
>>>
>>>
>>>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>>
>>>
>>>>apple"; however, it makes perfect sense to say "This orange is not that
>>>
>>> ^^^^^^
>>> I would substitute 'Similarly, it makes no sense to say "This
>>>orange is less than that apple", unless we have defined a less than
>>>operator.' For example, the comparison might be of weight or of cost.
>>
>>But then the question becomes: "Is this weight less than that weight?"
>>and "Is this cost less than that cost?" which are completely different
>>questions.
> > > One is a question WITHOUT a defined answer. > One is a question WITH a defined answer. > > Asking the first type of question is pointless. > > [snip]
What if the point is to determine whether it has a defined answer? Received on Tue Jan 09 2007 - 21:53:28 CET