it would be interested to know if @: performs better than [: in general. 

On May 16, 2013, at 11:48 AM, Roger Hui <[email protected]> wrote:

> I don't know why ([:-.-:)"0/ ?2 100000$10 is slower than (-.@:-:)"0/ ?2
> 100000$10.  To find the answer I'd have to look at the code.  I am not
> surprised that they run at different speeds because [:-.-: and -.@:-: are
> implemented by different code.
> 
> +/@:, requires less space than [:+/, because the former is recognized as
> special code but the latter isn't.  There is a section of code for atop and
> another one for fork, including capped forks, and it is in those codes that
> special codes are recognized.  More specifically, +/@:,x is recognized when
> it is interpreting +/@:, , not when it eventually sees the x.  That is, if
> you say sumravel=:+/@:, and then apply sumravel multiple times, the special
> code recognition happens only once.  Given that, you can readily imagine, I
> think, how differences can arise in such a thing as special code
> recognition and thence in performance.
> 
> 
> 
> 
> On Thu, May 16, 2013 at 6:02 AM, Thomas Costigliola <[email protected]>wrote:
> 
>> On Tue, May 14, 2013 at 2:49 PM, km <[email protected]> wrote:
>> 
>>> Roger provides a motivation for capped fork in his Wiki essay Capped
>> Fork:
>> http://www.jsoftware.com/jwiki/Essays/Capped%20Fork?highlight=%28completeness%29
>>> 
>>> He says, "When [: g h is interpreted as g@:h ,  it means that
>>> "everything" can be expressed as a fork (ordinary and capped)."
>>> 
>>> However, it appears that [: g h is not always interpreted as g@:h. Two
>> simple examples:
>> 
>>   10 (6!:2) '([:-.-:)"0/ ?2 100000$10'
>> 0.02305822671099
>>   10 (6!:2) '(-.@:-:)"0/ ?2 100000$10'
>> 0.003745674810987
>> 
>>   (7!:2) '([:+/,) i.2#1000'
>> 12584512
>>   (7!:2) '(+/@:,) i.2#1000'
>> 8390272
>> 
>> I wonder if there is a reason for that, i.e., should they not always be
>> interpreted the same because they are not according to the dictionary? Or
>> if it was an oversight.
>> 
>> 
>> I hope this teaser will make you eager to see his essay!
>>> 
>>> --Kip Murray
>>> 
>>> Sent from my iPad
>>> 
>>> 
>>>> On Mon, May 13, 2013 at 9:56 PM, Jose Mario Quintana
>>>> <[email protected]> wrote:
>>> 
>>>> A teaser cap is the exception to the
>>>>> 
>>>>> rule, [: is the only verb that is not invoked when is the leading verb
>>> in a
>>>>> fork, for no compelling reason (again, from my viewpoint).
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