Comma is not always OK in the argument list?!

[Nick Vatamaniuc]

True, that is why it behaves the way it does, but which way is the
correct way? i.e. does the code need updating or the documentation?

-Nick V.

olsongt at verizon.net wrote:
> Nick Vatamaniuc wrote:
> > Roman,
> >
> > According to the Python call syntax definition
> > (http://docs.python.org/ref/calls.html) commas should be allowed, so it
> > seems like a minor bug.  Here are the  lines in question:
> > -----http://docs.python.org/ref/calls.html-----------
> > call ::= primary "(" [argument_list [","]] ")"
> > argument_list::=positional_arguments ["," keyword_arguments] ["," "*"
> > expression] ["," "**" expression]
> > 	| keyword_arguments ["," "*" expression] ["," "**" expression]
> >         | "*" expression ["," "**" expression]
> >         | "**" expression
> > ----------------------------------------------------------
> > If you notice in the 'call' definition, no matter what the
> > 'argument_list' is, it can be followed by an optional ',' right before
> > the closing ')'. Your code is a counterexample to this. Here is a more
> > exhaustive example:
> > --------------------------------------------------------
>
> Actually, in the real BNF it's not allowed:
>
> http://svn.python.org/view/python/trunk/Grammar/Grammar?rev=46209&view=markup
>
> parameters: '(' [varargslist] ')'
> varargslist: ((fpdef ['=' test] ',')*
>               ('*' NAME [',' '**' NAME] | '**' NAME) |
>               fpdef ['=' test] (',' fpdef ['=' test])* [','])
> fpdef: NAME | '(' fplist ')'