On 1/31/2013 12:15 PM, MRAB wrote:
On 2013-01-31 16:35, Jason Keene wrote:
Why do function definitions require parens?
class MyClass: ... pass ... def my_func: File "<stdin>", line 1 def my_func: ^ SyntaxError: invalid syntax
This seems to me to break a symmetry with class definitions. I assume this is just a hold off from C, perhaps there is a non-historical reason tho.
I believe in the past we've forced parens in list comprehensions to create a symmetry between comprehensions/generator expressions. Why not for this?
The parentheses are always required when calling the function, so it makes sense to always require them when defining the function.
The case with class definitions is different; they are used in the definition only when you want to specify the superclass.
I think parens for super class are an unfortunate syntax, since it looks just like arguments to the class and is confusing for some beginners: def function(arg): ... function(10) # Similar syntax: 10 corresponds to arg class Thing(Something): ... thing = Thing(10) # How does 10 relate to Something? It doesn't. A better syntax (which I AM NOT PROPOSING) would be: class Thing from Something: --Ned.
They are always required when creating an instance of the class and in method definitions. _______________________________________________ Python-ideas mailing list Python-ideas@python.org http://mail.python.org/mailman/listinfo/python-ideas