[Python-3000] Cleaning up argument list parsing (was Re: Morewishful thinking)

Wed Apr 19 23:42:01 CEST 2006

"Guido van Rossum" <guido at python.org> wrote in message 
news:ca471dc20604190650x39efc500p503807aa757c25a3 at mail.gmail.com...
> I once considered and rejected this syntax since another logical
> interpretation would be that any positional arguments are accepted but
> *ignored*.

I was about to suggest that perhaps this is how it should be interpreted 
;-).

Perhaps it is too much to use syntax to indicate whether positional args 
should be silently ignored or raise an exception.  Given

def f(*ignored, a, b='yes'): <body>

positional args will be ignored if 'ignored' if never referenced again.  To 
raise an exception, just add

  if ignored: raise TypeErrror("Positional args not allowed")

Given that keyword only functions should be fairly rare (given that we have 
survived thus long without), is a syntactic abbreviation needed?

Terry Jan Reedy