Hi Hans-Peter,
see below.
On 3/1/26 17:49, Hans-Peter Sorge wrote:
Hi Jürgen,
-for 1- In file native/template.hhthe comment states:
// mandatory functions
....
static Token *eval_fill_B*(Value_P B, const NativeFunction * caller);
However there is a fill function for argument B in template_f0:
#if defined TEMPLATE_F0
...
get_function_mux(const char * function_name)
{
....
if (!strcmp(function_name, "*eval_fill_B*"))
return reinterpret_cast<void *>(&*eval_fill_B*);
....
Compile without * if ... eval_fill_B .. * is OK
-for 2- in src/ScalarFunction.cc
it says
/* *eval_fill_B()* is called for:
1. a monadic scalar function with empty B, or ...
...
The Qs:
-1- F0 is niladic. What are the circumstances that *eval_fill_B()*
could get called?
Supposedly never. The *function_mux()* of the native function maps a
function
name string like *"eval_fill_B"*) to a function pointer like
*eval_fill_B()* that can
be called.
To keep things simple, the *function_mux()* is independent of the arity
of the function.
fill functions are either monadic or dyadic, therefore niladic functions
don't have one.
One could remove the calls to *eval_fill_B()* and *eval_fill_AB()* in
the *get_function_mux()
*in *template.hh* but then you have different function_muxed for
different arities which
is merely complicating matters without an obvious advantage.
-2- A monadic call to F12('lib_template_F12.so' ⎕FX 'F12')
with an empty B does not call *eval_fill_B(). *Why not?
F12 'b'
eval_B() called
⍝ as expected
F12 ⍬
eval_B() called
⍝ *eval_fill_B() called* expected too
No The eval_Fill_B function is not called for any empty B but only for
empty arguments of particular functions (most prominently for reduction or
scan of functions with empty arguments). The IBM APL2 reference manual
contains a list of functions and operators for which the fill functions are
being called.
I suppose that *F12 / ⍬* will say that the fill function was called.
What am I missing?
Best Regards
Hans-Peter
