Re: [Bug-apl] Implementing Dyalog Key function

[Elias Mårtenson]

The key function is better described in the Dyalog reference manual, on page 153 here: http://docs.dyalog.com/16.0/Dyalog%20APL%20Language%20Reference%20Guide.pdf

Essentially, it's a grouping function. It's used to create groups of similar things, and apply a function on the individual instances. The examples in the section I referenced above should be pretty clear, I think.

Regards,

Elias

On 3 July 2017 at 00:51, Juergen Sauermann <address@hidden> wrote:

Hi Elias,

I am not quite in favour of it and it has problems.

It is not on my keyboard (even though I am using a Dyalog keyboard).
Not to talk about other keyboards.

It does not really look like need-to-have function and I suppose it can be
efficiently performed by a short combination of other APL primitives.

In my opinion adding primitives for every imaginable use case (and
there are certainly use cases for the key function) leads to an overloading
of the APL language in the long run and does not improve the language.

Another problem is that after reading the description several times, I still
can't explain in simple terms what the function is actually doing.  That makes it
a good candidate for a never used function if it should ever be implemented.

Best Regards,
Jürgen Sauermann

On 07/02/2017 06:24 PM, Elias Mårtenson wrote:

How about implementing the key function, ⌸?

It's described in this article on the Dyalog site: https://www.dyalog.com/blog/2015/04/exploring-key/

Jürgen, are you in favour of this function?

Regards,

Elias