Re: [Bug-apl] crash on each of empty

[David B. Lamkins]

Thank you. Confirmed working with the original test cases.

Pushing a bit further, I believe that the following behavior may still
be contrary to the IBM spec in SVN 268:

      +¨''
┌⊖┐
│0│
└─┘

Here we have a numeric function passed an empty character. Transforming
this via the identity given previously, we get the equivalent
expression:

      (⍴'')⍴⊂+↑''
DOMAIN ERROR
      (⍴'')⍴⊂+↑''
             ^^

(I don't know whether there's a corresponding case for ⍬. Is there a
primitive monadic function that only accepts character arguments?)


On Thu, 2014-05-15 at 12:22 +0200, Juergen Sauermann wrote:
> Hi,
> 
> thanks, hopefully fixed in SVN 268. Also the debug printouts.
> 
> /// Jürgen
> 
> 
> On 05/14/2014 07:01 PM, David B. Lamkins wrote:
> > I think Elias is correct.
> >
> > >From the IBM manual, pg. 110 (check the source; I think I've transcribed
> > accurately, but make no guarantee):
> >
> > -- begin
> > Empty Argument: If R is empty, the function LO is not applied. Instead,
> > a related function called the fill function of LO is applied with
> > argument ↑R (the prototype of R). This result is used as a prototype of
> > the empty array of ρR .
> >
> > The identity is:
> >    LO¨ ̈R ←→ (ρR)ρ⊂fill fn ↑R
> >
> > where:
> >    LO       Is any function for which a fill function is defined
> >    fill fn  Is its related fill function
> > -- end
> >
> > That'd mean:
> >
> >    +¨⍬   ←→ ⍬
> >    ,¨''  ←→ ''
> >
> > Also, in the case where a function is a defined function, its fill
> > function is the identity function. Therefore {⍵}¨'' and {⍵}¨⍬ should
> > behave according to these identities:
> >
> >        (⍴'')⍴⊂{⍵}↑''
> > ┌⊖┐
> > │ │
> > └─┘
> >        (⍴⍬)⍴⊂{⍵}↑⍬
> > ┌⊖┐
> > │0│
> > └─┘
> >
> > On Thu, 2014-05-15 at 00:14 +0800, Elias Mårtenson wrote:
> >> I tested this, and I'm wondering if the return value should really be
> >> 0? Wouldn't it make more sense to return ⍬?
> >>
> >>
> >> Regards,
> >> Elias
> >>
> >>
> >>          
> 
>