Re: pre-PEP: Suite-Based Keywords

[Brian Sabbey]

Shane Hathaway wrote:
Kent Johnson wrote:
Brian Sabbey wrote:
Using suite-based keyword arguments, the code
f(x = 1)
is equivalent to
f():
   x = 1

ISTM the syntax is ambiguous. How do you interpret
if f():
  x = 1
?
Is a suite alllowed only when a block could not be introduced in the
current syntax?
I like this PEP a lot, but your concern is valid.  Maybe Brian could
modify the PEP slightly to disambiguate.  How about using an ellipsis in
the argument list to signify suite-based keywords?  Examples:
f(...):
   x = 1
class C(object):
  x = property(...):
     doc = "I'm the 'x' property."
     def fget(self):
        return self.__x
     def fset(self, value):
        self.__x = value
     def fdel(self):
        del self.__x
d = dict(...):
   a = 1
   b = 2
Using an ellipsis in a statement that would begin a different kind of
block is illegal and generates a syntax error.  Note that this usage
seems to fit well with the definition of "ellipsis".
http://dictionary.reference.com/search?q=ellipsis
Shane
Yes, my description of the syntax was ambiguous.  To clarify, I intended 
the syntax to be backwardly compatible.  That is, one would not be able to 
use a suite to define keywords if there already exists a suite for other 
reasons.  So, one would not be able to use a suite to pass keywords to 'f' 
in this situation:

if f():
     x = 1
This code should behave exactly as it does now.
I agree that the ellipsis idea probably makes the code more readable, and 
it may be a good idea to have them for that reason.  However, ellipses are 
not necessary as a way to disambiguate the syntax; all statements 
containing suites currently begin with a keyword, and keyword suites would 
not.

-Brian
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