[Jprogramming] joining to an empty list

[Henry Rich]

([: u v)"v y    is u at v .

For & you have

x u&:v y <=> (v x) u (v y)  <=>  x (v@[ u v@]) y

and

u&v <=> u&:v"mv    where mv is ({. v b. 0)


You are making your understanding very difficult - in fact, perhaps 
impossible - by trying to do everything wuth [: . @, @:, &, &: are all 
different.  If [: were all you needed, maybe Ken would have left out the 
others.

Henry Rich

On 1/12/2013 8:50 PM, Linda Alvord wrote:
> Thanks David, Kip and Rich
>
> My concern is that it is too hard to find the alternative when the simple
> definition doesn't work.
>
> u&v y ->  ([: u v)"v y
> As long as the ranks agree,  u&v y -> u v y
>
> Would this be useful as a definition of compose?
>
> Linda
>
>
> -----Original Message-----
> From: programming-bounces at forums.jsoftware.com
> [mailto:programming-bounces at forums.jsoftware.com] On Behalf Of Henry Rich
> Sent: Saturday, January 12, 2013 8:17 PM
> To: programming at jsoftware.com
> Subject: Re: [Jprogramming] joining to an empty list
>
> What he's saying (& Kip earlier) is, when you wrote
>
> ([: u v y)"v
>
> you meant
>
> ([: u v)"v y
>
> because
>
> ([: u v y)
>
> gives a domain error.
>
> Henry Rich
>
> On 1/12/2013 7:48 PM, Linda Alvord wrote:
>> David, I don't understand the concern you are raising
>>
>> u&v y ->  ([: u v y)"v
>> As long as the ranks agree,  u&v y -> u v y
>>
>>
>>      ]A=:'one';'two';'three'
>> ----T---T-----┐
>> │one│two│three│
>> L---+---+------
>>      #&>A
>> 3 3 5
>>      ([:#>)">A
>> 3 3 5
>>
>> In this case there is no domain error. Is there a different context
>> when you will get a domain error?
>>
>> Thanks in advance:Linda
>>
>>
>> -----Original Message-----
>> From: programming-bounces at forums.jsoftware.com
>> [mailto:programming-bounces at forums.jsoftware.com] On Behalf Of David
>> Ward Lambert
>> Sent: Saturday, January 12, 2013 3:43 PM
>> To: programming
>> Subject: Re: [Jprogramming] joining to an empty list
>>
>> The vocabulary should not say
>> u&v y ->  ([: u v y)"v
>> because
>>      [: verb verb NOUN
>> is a domain error.
>>
>> ----------------------
>> Subject: Re: [Jprogramming] joining to an empty list
>> Message-ID: <000e01cdf0d4$4d3da130$e7b8e390$@net>
>> Content-Type: text/plain; charset=utf-8
>>
>> Here's a sentence that I think would be more helpful in the vocabulary:
>>
>>        ]A=:'one';'two';'three'
>> ???????????????
>> ?one?two?three?
>> ???????????????
>>      #&>A
>> 3 3 5
>>      ([:#>)">A
>> 3 3 5
>>                       ^
>>      NB. Then shouldn't the vocabulary say   u&v y ->  ([: u v y)"v
>>
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