What is the meaning of the astarisk in Python

[John Dean]

Hi
Below is a line taken from Andy Dustman's MySQLdb module:
def Connect(*args, **kwargs):

I would be grateful if somebody explain the meaning of the astarisks, since
I was under the impression that pointers are not used in Python and the
above look very must like pointers to me

 

[John Roth]

Hi
Below is a line taken from Andy Dustman's MySQLdb module:
def Connect(*args, **kwargs):

I would be grateful if somebody explain the meaning of the astarisks, since
I was under the impression that pointers are not used in Python and the
above look very must like pointers to me

One asterisk creates a list of all positional arguements,
two asterisks creates a dictionary of all keyword arguements.
"All" means "not otherwise represented in the parameter list."

John Roth

 

[Andrei]

They're both shortcuts for specifying parameters. args is a tuple of
positional arguments, kwargs is a dictionary of keyword arguments.
Like this:



... print args

...

(3, 4, 'c')

... print kwargs

...

{'a': 3, 'b': 4}

... print args, kwargs

...

(2, 3) {'c': 5, 'd': 6}

(2, 3) {}

() {'c': 5, 'd': 6}


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[Bob Gailer]

At 06:13 PM 9/20/2003, John Roth wrote:

One asterisk creates a list of all positional arguements,

Do you mean tuple?

two asterisks creates a dictionary of all keyword arguements.
"All" means "not otherwise represented in the parameter list."

Bob Gailer
(e-mail address removed)
303 442 2625

 

[Michael Peuser]

Hi
Below is a line taken from Andy Dustman's MySQLdb module:
def Connect(*args, **kwargs):

I would be grateful if somebody explain the meaning of the astarisks, since
I was under the impression that pointers are not used in Python and the
above look very must like pointers to me

In addition to the other answers:
It also works the other way: You can use tuples ore dicts for positional or
keyword parameters. This generally comes handy for co-ordinates in graphic
routines.

def p(a,b,c,d, x=None,y=None):
print a,b,c,d,x,y

abcd=(1,2,3,4)
xy={'x':100, 'y':200}

p(*abcd)
p(0,0,0,0,**xy)


Kindly
MichaelP

 

[Lee Harr]

Hi
Below is a line taken from Andy Dustman's MySQLdb module:
def Connect(*args, **kwargs):

I would be grateful if somebody explain the meaning of the astarisks, since
I was under the impression that pointers are not used in Python and the
above look very must like pointers to me

http://python.org/doc/current/tut/node6.html#SECTION006600000000000000000
http://python.org/doc/current/tut/node6.html#SECTION006720000000000000000
http://python.org/doc/current/tut/node6.html#SECTION006730000000000000000