Re: [Bug-apl] Revisiting the APL 2 empty-array display behavior

[Juergen Sauermann]

Hi,

output formatting is one of the most challenging tasks
in an APL2 interpreter. The rules governing this are spread
over different chapter in the APL2 language reference and
seem to be different in the ISO standard. Even the examples
in the language reference and in the standard differ occasionally.

I have tried to emulate IBM APL2 as good as possible, but some
differences may still exist.

The method for discarding a value Z seems to be 0 0⍴Z instead
of 0⍴Z these days. A smarter one could be monadic ⍪ ("table")
which turns an empty vector into an empty matrix (as does 0 0⍴).

/// Jürgen


On 05/29/2014 02:55 AM, David B. Lamkins wrote:

On Wed, 2014-05-28 at 18:11 -0500, Blake McBride wrote:

Dear David,


Thanks for the idiom reference!

You're welcome. :)

With a lot of respect, I think you missed my point.  The APL 1 idiom
works as you want and expect in APL 1, APL 2, and GNU APL.  Look
closely at my example.


On the other hand, if it is I who is missing the point (quite
possible), please explain.

No, you're entirely correct. I misunderstood what I was seeing in a
different context, I think.

Not enough sleep... :(

Thanks again.