Re: [Bug-apl] Feature suggestion: multiple function arguments

[Peter Teeson]

Hi Jürgen:

Thanks for your patience… I am probably still somewhat stuck in my time-sharing mainframe days.

If I understand you correctly you are saying that I can make a shared library let’s say with a name ⌶?

I haven’t tried making such a named library/plugin - Is it going to be possible to name it using the ⌶ symbol?

e.g. On my keyboard using MacAplAlt as a keyboard source it’s 

option+shift+1 i.e. Unicode U+2336 ( which is the APL functional symbol I-Beam).

Presently GNU APL gives me "No token" when I enter it.

Then ⎕FX it and have an apl _expression_ X⌶Y and another apl _expression_ Xº∘Y?

Where the 2nd _expression_ uses the GNU APL outer product implementation and the first uses my implementation?

( ⌶ could be an implementation of train, or fork, or whatever a programmer would like to try as a language extension

or operator speedup or more advanced algorithm, or non homogenous arrays because nested is not elegant, etc).

Suppose it is — will the GNU APL interpreter then recognize it as a token and 

 "call into my library" passing me the environment? 

Which is what I would like it to do. This is the key question and idea that I am proposing …..

Which is why the ⌶ symbol gets parsed in the interpreter as though it were an apl symbol.

In ⌶ will I have access to the stack, heap, and so on?

Of course that’s dangerous and one must be well behaved but that’s true now isn’t it? 

On the mainframe you had to be at physically at one of the 3 or 4 operator consoles plus also be privileged.

IOW like root on Unix systems - sudo s. Of course on single user systems being root is not really necessary.

If so maybe your suggestion works for me because the _expression_ X⌶Y looks aplish.

Anyway that’s what I have been thinking / imagining….. 

respect…

Peter

On Mar 16, 2016, at 1:36 PM, Juergen Sauermann <address@hidden> wrote:

Hi Peter,

I am not quite getting why you would need the I-beam thing in the first
place (or why you would need to involve the parser).

If all you want is to write something in assembler (and then call it from APL), then

- Pick a suitable user-defined name for it,
- Put the assembler (or C or FORTRAN or whatever) into a shared library,
- ⎕FX the shared library under the chosen name

From then on a call to the name will call the assembler code, passing the arguments
given to the assembler code and it will return the result produced by the assembler code.

No need for new ⎕AV symbols or ⎕-names or I-beams or such.

That IS a plugin in the form of a shared libraries. Many plugins are build like this these days.

And it works already!

/// Jürgen