[Jprogramming] why=: 13 :'y*y*y'

[Devon McCormick]

It's not a good advertisement for J when something so simple is so
clearly wrong.  I would certainly rank fixing an obvious bug over,
say, a performance improvement in a little-used feature like look-up
of symbolic names.

On Sat, Mar 17, 2012 at 1:26 PM, Tracy Harms <kaleidic at gmail.com> wrote:
> To clarify, I do think 13&: could be improved. I think your examples can
> help with that. I don't find flaws in this modifier very interesting among
> possible improvement efforts.
> On Mar 17, 2012 3:45 AM, "Linda Alvord" <lindaalvord at verizon.net> wrote:
>
>> David Ward Lambert pointed out the known pitfall that occurs using  : 13 :
>>
>>
>>
>> Would these examples help in correcting the problem?
>>
>>
>>
>>   why=: 13 :'y+y'  NB. wrong
>>
>>   why
>>
>> +
>>
>>   why 3
>>
>> 3
>>
>>   why=: 13 :'y-y'  NB. right
>>
>>   why
>>
>> -~
>>
>>   why 3
>>
>> 0
>>
>>   why=: 13 :'y*y'  NB. wrong
>>
>>   why
>>
>> *
>>
>>   why 3
>>
>> 1
>>
>>   why=: 13 :'y%y'  NB. right
>>
>>   why
>>
>> %~
>>
>>   why 3
>>
>> 1
>>
>>   why=: 13 :'y+y+y' NB. wrong
>>
>>   why
>>
>> ] + +
>>
>>   why 3
>>
>> 6
>>
>>   why=: 13 :'y-y-y'  NB. right
>>
>>   why
>>
>> ] - -~
>>
>>   why 3
>>
>> 3
>>
>>   why=: 13 :'y*y*y'  NB. wrong
>>
>>   why
>>
>> ] * *
>>
>>   why 3
>>
>> 3
>>
>>   why=: 13 :'y%y%y'  NB. right
>>
>>   why
>>
>> ] % %~
>>
>>   why 3
>>
>> 3
>>
>>
>>
>> Linda
>>
>>
>>
>>
>>
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>>
> ----------------------------------------------------------------------
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-- 
Devon McCormick, CFA
^me^ at acm.
org is my
preferred e-mail