simple answer: {3} is niladic in GNU APL (since lack of ⍵) and monadic
(why?) in Dyalog et al.
To get the Dyalog behaviour in GNU APL use {3⊣⍵} instead of {3}:
{3⊣⍵} ¨⍳5
3 3 3 3 3
That makes the lambda monadic in GNU APL and discards its argument
like Dyalog does. You will get the same SYNTAX ERROR in Dyalog if you
call EACH with a niladic function (except that it can't be a lambda then):
⎕FX 'Z←FOO' 'Z←3'
FOO¨⍳5
SYNTAX ERROR
FOO¨⍳5
∧
I personally believe that there should be no differences between "normal"
defined functions (with ⎕FX or the ∇-editor) and lambda, but that opinion
is not shared unanimously.
Best Regards,
Jürgen
On 1/3/21 2:32 PM, Otto
Diesenbacher-Reinmüller wrote:
Dear APLers, I don't think this is a bug, but intentionally:Doing f.e.: { 3 } ¨ ⍳5 results in gnu-apl to an error: SYNTAX ERROR λ1¨⍳5 ^ ^ In other APLs, this works just fine, f.e. dyalog (or even april): { 3 } ¨ ⍳5 3 3 3 3 3 More general without Each/¨, f.e. { 3 } 55 results in gnu-apl in 3 55 but in dyalog (and others) in 3 What's the background of this different behavior in gnu-apl? I also couldn't find any hint in IBMs APL2 Reference for this behavior. br & and many thanks for any hint! br Otto
