On 5 March 2016 at 19:12, Juergen Sauermann <juergen.sauerm...@t-online.de>
wrote:
> Hi Alexey,
>
> the IBM APL2 binding rules say that [] binds stronger than vector notation
> (IBM APL2
> language reference page 34). That is,
>
> *100 200[1] *is* 100 (200[1])*
>
> IBM APL2 behaves in the same way as GNU APL.
>
At first I was confused about this (and even started writing this email
expressing that confusion). Then I realised that it is Dyalog that must
have a very bizarre evaluator.
What does the following do in Dyalog?
a ← 1
2 a[1]
If vector notation binds string that dereference, then this should return 2.
But if that is the case, what does the following return?
b ← ⍳5
9 8 b
9 8 b[2]
Again, if Dyalog is consistent, it should return 8, and not 9 8 2 which is
the case in GNU APL.
However, if Dyalog returns the same value as GNU APL, that means that the
parser changes the binding strength depending on the type of arguments.
That sounds incredibly weird to me.
Regards,
Elias
