[Jprogramming] atop continues to puzzle me

[Raul Miller]

By "definition" I specifically mean "verb definition" which means: the
behavior (domain, range, rank, mapping) of the verb in the monadic
case and the dyadic case.  Also, in the general case "definition"
would also include any noun, adverb or conjunction definitions.

In this case, the verb definition of 'at' is used only within the
context of the d. definition -- to make at d. 1 and @ d. 1 be
identical we would need to fix the definition of d.

-- 
Raul

On Wed, Jan 9, 2013 at 5:37 PM, Jose Mario Quintana
<jose.mario.quintana at gmail.com> wrote:
> Sure, if you do not make use of d. is insignificant. However, difference in
> behavior because of context could cause a production system to crash and
> that would be very significant to me; being extra careful (trust but
> verify), in my experience, has prevented grim consequences in similar
> circumstances.
>
> I am curious: What you do exactly mean by "Here's a definition for at which
> works exactly like @"?
>
> On Fri, Jan 4, 2013 at 11:00 AM, Raul Miller <rauldmiller at gmail.com> wrote:
>> On Thu, Jan 3, 2013 at 5:53 PM, Jose Mario Quintana
>> <jose.mario.quintana at gmail.com> wrote:
>>>> Here's a definition for at which works exactly like @
>>>>
>>>>    at=: 2 :'([: u v)"v
>>>
>>>
>>> Rather works almost exactly?
>>>
>>>    ('*'"_) @ ((+: @ *:) (d.1)) (0 1 2)
>>> *
>>>    ('*'"_) @ ((+: at *:) (d.1)) (0 1 2)
>>> ***
>>>
>>>    ((+: @ *:) (d.1)) b.0
>>> _ _ _
>>>    ((+: at *:) (d.1)) b.0
>>> 0 0 0
>>
>> Here, we are no longer comparing the definitions of @ and at
>>
>>    ((+: @ *:) (d.1))
>> 0 4x&p.
>>    ((+: at *:) (d.1))
>> 0 4x&p."0 0 0
>>
>> Instead, it's the working of d. that is significant here.
>>
>> Here's another case where @ and at are different, and I feel that the
>> significance of this case is similar to the significance of the d.
>> case (though obviously they are not identical cases):
>>
>>    '@' -: 'at'
>> 0
>>
>> --
>> Raul
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