Function wrapper in Python

[Alex Martelli]

<Olav.Benum at bigfoot.com> wrote in message
news:39E1F408.A03AF6E7 at yahoo.com...
>
>  I would like to write a function-wrapper that takes a
>  function and its arguments as arguments, redirect
>  output, and calls the function within a try/catch
>  block.  Something like:
>  def function_wrapper( funcname, *name **unnamed):
>          try:
>                funcname( name, unnamed )#??
>          except OSError,error:
>                  print "General exception"
>                  if error:
>                          print str(error)

All of these arguments are misleadingly named (the first
one, as shown from later example, is a function and NOT
a function-name, etc), but, anyway:

def function_wrapper(thefunc, *args, **kwds):
    try:
        return apply(thefunc, args, kwds)
    except OSError, error:
        print "General exception"
        if error: print str(error)


In Python 2.0 you can change the return-line to:

        return thefunc(*args, **kwds)

but that's not much of an advantage, in this case,
over using the builtin function apply, so I'd
suggest using apply anyway.


>  (Ideally I would like something like having an abstract
>  base-class with the function name as an abstract method,
>  from this I would derive a class for my function, and
>  then call the init function like FucntionInstance(
>  Arguments)

Sorry, but this part of your request is not very clear to
me.  It's certainly feasible to wrap a function through a
class instance, or to wrap a class instance, etc, but what
you exactly want, I can't quite fathom -- also, again I
think I see some confusion between a function and its name.

Maybe if you post a complete, short example of code where
you would like to USE the desired construct, as you did
for the function-wrapping-function case, we could help...


Alex