rlib-devel

[Rlib-devel] Rlib and python interface

[William K. V. <wk...@us...>]

Hello,
	I've been playing with Rlib for a couple of days and
been successful at getting some quick reports done.  One
problem I noticed was that rlib_get_output was not working
when images were included in reports.  Although it appears
that the python interface was originally done with SWIG I
didn't find the interface files.  My hope is that you've
only used SWIG to get the initial interface done and that
moving forward, changes would be made by editing the
python.c file.  Is that correct?  If so I would be willing
to spend some time cleaning up the python interface and
perhaps making it more "pythonic".  Anyway the fix to
get_output was trivial, patch attached.

Thank you,
William.

Re: [Rlib-devel] Rlib and python interface

[Bob D. <bd...@si...>]

Hi,

Patch looks correct.  Right now I only maintain the PHP bindings by
hand.  

Right now there are a few things the Python(And other SWIG Interfaces)
interface doesn't have, would you be willing to do any of these?  I have
manually done these in PHP

1) Array Data Source:  Use a 2D array as a data source

2) Signals/Callbacks:  Right now in PHP we can attach to events in the
RLIB engine and it will call back to a PHP function to do whatever...

3) "m.xxx" environment variables.  In PHP it looks at the global symbol
table for xxx and gets the value it needs

4) Custom functions.  Add custom functions to the engine that RLIB does
not provide.  So in PHP:

rlib_add_function($rlib, "test", "test_function", 2);

function mike_roth($a, $b) {
	return "pancakes are yummier then $a and $b";
}

Then in the RLIB XML:

you would do: ..... value="test('bacon', 'eggs')"

======

Obviously if you did these things I would start making the bindings by
hand in the future (Normally it's a copy and paste job)

Also, just out of curiosity what are you trying to use RLIB for?

- Bob

Re: [Rlib-devel] Rlib and python interface

[William K. V. <wk...@us...>]

Hello Bob,
On Sun, 2005-06-05 at 08:22, Bob Doan wrote:
> Patch looks correct.  Right now I only maintain the PHP bindings by
> hand.  
> 
> Right now there are a few things the Python(And other SWIG Interfaces)
> interface doesn't have, would you be willing to do any of these?  I have
> manually done these in PHP
These all look doable, I will have to do a little research on how to
implement the callbacks though, I don't think it will be too hard.

> 1) Array Data Source:  Use a 2D array as a data source
> 
> 2) Signals/Callbacks:  Right now in PHP we can attach to events in the
> RLIB engine and it will call back to a PHP function to do whatever...
> 
> 3) "m.xxx" environment variables.  In PHP it looks at the global symbol
> table for xxx and gets the value it needs

Should be easy.

> 
> 4) Custom functions.  Add custom functions to the engine that RLIB does
> not provide.  So in PHP:
> 
> rlib_add_function($rlib, "test", "test_function", 2);
> 
> function mike_roth($a, $b) {
> 	return "pancakes are yummier then $a and $b";
> }
> 
> Then in the RLIB XML:
> 
> you would do: ..... value="test('bacon', 'eggs')"
> 
If/when I get callbacks working this could naturally fall out of that.

> 
> Obviously if you did these things I would start making the bindings by
> hand in the future (Normally it's a copy and paste job)

My experience with SWIG is that it can be a quick way to get a prototype
set of bindings however in the long run, for stability, it is best to
switch to an interface developed specifically for the library.  The
pro-dominant reasons being object reference counting and memory
management.  Boost did a better job however is C++ and then of course
there is the strange C+python meld of Pyrex.

> Also, just out of curiosity what are you trying to use RLIB for?

We are a small startup company doing electronic transaction processing
and because of my work load we just hired a programmer to develop
reporting however accounting was having a nightmare trying to reconcile
our bank transactions to daily processing.  I was looking for a quick
way to get a report done, found rlib, and tried it.  It worked great ;-)
I usually hack code on the weekends to keep me relaxed so I thought
I could offer to build a custom python interface for you.

Thanks, 
William.