Python Pocket Reference, Second Edition

Name

Expressions

Synopsis

expression
function([value, name=value, ...])
object.method([value, name=value, ...])

Any expression can appear as a statement (but statements cannot appear as expressions). Expressions are commonly used for running functions and for interactive-mode printing.

In function and method calls, actual arguments are separated by commas and are normally matched to arguments in function def headers by position. Calls may optionally list specific argument names in functions to receive passed values, by using the name=value keyword syntax.

apply( )-like call syntax

As of Python 2.0, special syntax can be used in function and method call argument lists to achieve the same effect as an apply( ) built-in function call. If args and kw are a tuple and a dictionary, respectively, the following are equivalent:

apply(f, args, kw)
f(*args, **kw)

Both formats call function f with positional arguments args and keyword arguments kw. The latter format is intended to be symmetric with function header arbitrary-argument syntax such as def f(*args, **kw):.