Re: [Bug-apl] Lambda valence error

[Daniel H. Leidisch]

Hello!

Christian Robert
<address@hidden> writes:

>       ∇z←OMEGA n
> [1] z←n
> [2] ∇
>       1 OMEGA 2
> VALENCE ERROR
>       1 OMEGA 2
>       ^ ^
>       1 (OMEGA 2)
> 1 2

As I said in my other answer, what I meant was that

      1 {⍵} 2
2

works in both Dyalog and NGN. I.e. the lambda can be used monadically
/and/ dyadically without containing ⍺.

> so, it's not related to Lambda functions at all. The parser may be, or
> working as designed ...

It depends on the semantics of lambda functions, but since the docs say
that "If only ⍵ is present then it is monadic, and if neither ⍺ nor ⍵ is
present then the lambda is niladic", I agree that it's probably intended
behavior.

The thing is, I /thought/ that this used to work as in Dyalog and NGN,
because I have some notes with snippets depending on that behavior and I
usually make a comment when something only works for specific
implementations. I suppose I was just sloppy when making my notes and
that my memory is deceiving me here. (By the way, NARS2000 behaves like
GNU APL.)


Regards,

Daniel