Re: [Bug-apl] Execute gives incorrect VALUE ERROR

[Elias Mårtenson]

Changing it to work is quite trivial though. All you have to do is to append ◊ ⍬ to the _expression_. I.e:

      ⍎'foo'

Becomes:

      ⍎'foo ◊ ⍬'

Regards,

Elias

On 24 May 2014 13:58, Blake McBride <address@hidden> wrote:

I have code that depends on it, and it is a technique I used for years.  I wrote an APL function editor in APL 30 years ago.  I discovered the problem while entering the system into GNU APL.  I used this code in IBM APL.

On Fri, May 23, 2014 at 11:20 PM, David B. Lamkins <address@hidden> wrote:

This is ambibiguous w.r.t. the two spec on which GNU APL is based.

Page 120 of the IBM Reference Manual says:

"Valueless _expression_: If R is empty or represents a defined function or
operator without explicit result, R has no value."

Page 135 of the ISO Spec says:

"Informal Description: Z is the result of evaluating the character
scalar or vector B as a line of APL."


So the IBM spec allows an _expression_ which doesn't return a value; the
ISO spec doesn't.

Personally, I find the IBM definition to be more accommodating of the
behaviors I'd like to see.

On Fri, 2014-05-23 at 15:24 -0500, Blake McBride wrote:
>       )CLEAR
> CLEAR WS
>       ∇fun
> [1] 'in fun'
> [2] ∇
>       ⍎'fun'
> in fun
> VALUE ERROR
>       fun
>       ^
>