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

[David B. Lamkins]

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
> 
> 
> On 15 May 2014 00:02, Juergen Sauermann
> <address@hidden> wrote:
>         Hi David,
>         
>         thanks, fixed in SVN 266.
>         
>         /// Jürgen
>         
>         
>         
>         On 05/14/2014 01:56 AM, David B. Lamkins wrote:
>                 SVN Revision: 264
>                 
>                 
>                 
>                        {⍵}¨''
>                 
>                 
>                 ====================================================
>                 SEGMENTATION FAULT
>                 
>                 ----------------------------------------
>                 -- Stack trace at main.cc:122
>                 ----------------------------------------
>                 0x7f97fe168d65 __libc_start_main
>                 0x43557d  main
>                 0x52627d   Workspace::immediate_execution(bool)
>                 0x46418d    Command::process_line()
>                 0x46306f     Command::process_line(UCS_string&)
>                 0x44871e      Bif_OPER1_EACH::eoc_LB(Token&, EOC_arg&)
>                 0x45acc4       Cell::init_from_value(Value_P, char
>                 const*)
>                 0x45ab29        Cell::init(Cell const&)
>                 0x7f97ffe2a750
>                 0x47cf8a
>                 ========================================
>                 ====================================================
>                 
>                 Process apl segmentation fault (core dumped)
>                 
>                 
>                 
>                 
>                 
>                 
>                 and
>                 
>                 
>                 
>                 
>                 
>                        {⍵}¨⍬
>                 
>                 
>                 ====================================================
>                 SEGMENTATION FAULT
>                 
>                 ----------------------------------------
>                 -- Stack trace at main.cc:122
>                 ----------------------------------------
>                 0x7fa662bb1d65 __libc_start_main
>                 0x43557d  main
>                 0x52627d   Workspace::immediate_execution(bool)
>                 0x46418d    Command::process_line()
>                 0x46306f     Command::process_line(UCS_string&)
>                 0x44871e      Bif_OPER1_EACH::eoc_LB(Token&, EOC_arg&)
>                 0x45acc4       Cell::init_from_value(Value_P, char
>                 const*)
>                 0x45ab09        Cell::init(Cell const&)
>                 0x7fa664873750
>                 0x47cf8a
>                 ========================================
>                 ====================================================
>                 
>                 Process apl segmentation fault (core dumped)
>                 
>                 
>                 
>                 
>         
>         
>         
> 
>