Re: perlTK

[Joao Cardoso]

>On  4-Feb-2000, Joao Cardoso <address@hidden> wrote:
>
>| "John W. Eaton" wrote:
>| 
>| > On 31-Jan-2000, Joao Cardoso <address@hidden> wrote:
>| >
>| > | Couldn't Octave have a function to do it? Something like
>| > |
>| > |    on_idle("user function","user data")
>| >
>| > Sure, I've appended a solution.
>| 
>| Thanks!
>| 
>| But is seems that I have misunderstood its usage:
>| 
>| octave:2> function po(data); printf("%s\n",data);fflush(stdout);endfunction
>| octave:3> po("Hello")
>| Hello
>| octave:4> input_event_hook ("po","meee")
>| error: segmentation violation -- stopping myself...
>| 
>| I have tryed it with the last cvs. Hints?
>
>It worked when I first wrote it, but then I broke the event hook
>mechanism in liboctave when I was making changes to allow Octave to be
>compiled by compilers other than g++.
>
>Please try the following patch.


Thanks, it is now working OK.

However, I foresee a problem, if people/packages start using it, as
registering a new input function will overwrite the previous one.
I wrote two functions to avoid it and try to define a 'protocol'.

function register_input_event(func, data) register a new function
function deregister_input_event(func, data) de-register a function

I enclose them.

FYI, I am able to compile and run the latest Octave cvs (well, a few
days ago) with both egcs-1.1.2 and gcc-2.95.2 on sco-3.2v5.0.4.

Thanks,
Joao


function register_input_event(func, data)
 global __user_func__ __user_data__

# humm, check that arguments are strings, and that 'func' exists as a
function

 if (! exist("__user_func__"))
  __user_func__ = __user_data__ = list;
 endif

 __user_func__ = append(__user_func__, func);
 __user_data__ = append(__user_data__, data);

 if (length(__user_func__) != 0)
  input_event_hook("input_event","");
 endif

endfunction

function deregister_input_event(func, data)
global __user_func__ __user_data__
        
# humm, check that arguments are strings!

 if (! exist("__user_func__"))
  __user_func__ = __user_data__ = list;
  error("Nothing to de-register\n");
 endif

 for i=1:length(__user_func__)
  if (strcmp(nth(__user_func__,i), func) & strcmp(nth(__user_data__,i),
data)) 
   __user_func__ = splice(__user_func__, i, 1);
   __user_data__ = splice(__user_data__, i, 1);
   return
  endif
 endfor

 error("No match to de-register\n");
        
endfunction

# this function should be hided from the user

function input_event
 global __user_func__ __user_data__

 if (length(__user_func__) == 0)
  input_event_hook
 else
  for i=1:length(__user_func__)
   feval(nth(__user_func__, i), nth(__user_data__, i));
  endfor
 endif
        
endfunction

1;


function register_input_event(func, data)
global __user_func__ __user_data__
        
        if (! exist("__user_func__"))
                __user_func__ = __user_data__ = list;
        endif

        __user_func__ = append(__user_func__, func);
        __user_data__ = append(__user_data__, data);

        if (length(__user_func__) != 0)
                input_event_hook("input_event","");
        endif

endfunction

function deregister_input_event(func, data)
global __user_func__ __user_data__
        
        if (! exist("__user_func__"))
                __user_func__ = __user_data__ = list;
                error("Nothing to de-register\n");
        endif

        for i=1:length(__user_func__)
                if (strcmp(nth(__user_func__,i), func) & 
strcmp(nth(__user_data__,i), data)) 
                        __user_func__ = splice(__user_func__, i, 1);
                        __user_data__ = splice(__user_data__, i, 1);
                        return
                endif
        endfor

        error("No match to de-register\n");
        
endfunction

function input_event
global __user_func__ __user_data__

        if (length(__user_func__) == 0)
                input_event_hook
        else
                for i=1:length(__user_func__)
                        feval(nth(__user_func__, i), nth(__user_data__, i));
                endfor
        endif
        
endfunction