Re: [Bug-apl] A modest proposal: user-defined commands

[Juergen Sauermann]

Hi David, Peter,

I have added a simple facility for adding user defined commands (the command being
implemented in APL (possibly as native function)). I will no go as far as described in Dyalog's document below, however.

This could also be used for experimental commands or commands "missing" in GNU APL.

See ]HELP or 'info apl'. SVN 250.

/// Jürgen


On 05/03/2014 08:08 PM, David B. Lamkins wrote:

On Sat, 2014-05-03 at 15:02 +0200, Juergen Sauermann wrote:

Hi David,

from what I hear Dyalog APL seems to be a good interpreter and I have no 
problem with it.
I am only a little more conservative when it comes to new and 
non-standard APL features.
But Peter Teeson had ideas going into a similar direction.

I hope I didn't give the impression that I was casting aspersions on
Dyalog. They've taken APL in some new and interesting directions. All I
meant is that many of Dyalog's contributions to the language tend to be
outside of the canon of ISO/IBM APL 2.

One question that I have is how the implementation of a new command 
would look like.
Is it an APL function (which basically means that the command only 
relieves the user
from quoting the argument of the command) or would it be implemented in 
or C++
like native functions?

As I envisioned it: the former. Just some syntactic sugaring around an
APL function.

And do we know how often this feature in Dyalog was used in real life?

Its used to provide access to many of their development tools.

See http://docs.dyalog.com/13.2/User%20Commands.pdf .