Is it allowed to use function results as default arguments ?

[Stef Mientki]

hello,

I've a perfect working procedure,
at least as far I've tested it it works perfect.

But I was just experimenting with inspect,
and saw that the default argument was not parsed correctly.

So I wonder if this is allowed:

def Get_Relative_Pa th ( target, base=os.curdir ) :
...

As inspect returns the following:

(['target', 'base'], None, None, ('.',))

thanks,
Stef Mientki

[Simon Forman]

Re: Is it allowed to use function results as default arguments ?

On Jul 28, 1:28 pm, Stef Mientki <stef.mien...@g mail.comwrote:

hello,
>
I've a perfect working procedure,
at least as far I've tested it it works perfect.
>
But I was just experimenting with inspect,
and saw that the default argument was not parsed correctly.
>
So I wonder if this is allowed:
>
def Get_Relative_Pa th ( target, base=os.curdir ) :
  ...
>
As inspect returns the following:
>
(['target', 'base'], None, None, ('.',))
>
thanks,
Stef Mientki

os.curdir is '.' on many platforms. What did you expect inspect to
show?

|>>import os
|>>os.curdir
'.'

[Benjamin]

Re: Is it allowed to use function results as default arguments ?

On Jul 28, 3:28 pm, Stef Mientki <stef.mien...@g mail.comwrote:

hello,
>
I've a perfect working procedure,
at least as far I've tested it it works perfect.
>
But I was just experimenting with inspect,
and saw that the default argument was not parsed correctly.
>
So I wonder if this is allowed:
>
def Get_Relative_Pa th ( target, base=os.curdir ) :

Did you perhaps mean to say def Get_Relative_Pa th(target,
base=os.getcwd( )):

  ...
>
As inspect returns the following:
>
(['target', 'base'], None, None, ('.',))
>
thanks,
Stef Mientki

[fred.haab]

Re: Is it allowed to use function results as default arguments ?

Well, others have answered the question, but I thought I'd throw in
that it would be more pythonic to do something like:

def Get_Relative_Pa th(target, base = None):
if base is None:
base = os.curdir
...

[Ben Finney]

Re: Is it allowed to use function results as default arguments ?

"fred.haab" <fred.haab@gmai l.comwrites:

Well, others have answered the question, but I thought I'd throw in
that it would be more pythonic to do something like:
>
def Get_Relative_Pa th(target, base = None):
if base is None:
base = os.curdir
...

Even more Pythonic would be to name the function by the style guide
(PEP 8):

def get_relative_pa th(target, base=None):
if base is None:
base = os.curdir
# …

--
\ “If trees could scream, would we be so cavalier about cutting |
`\ them down? We might, if they screamed all the time, for no good |
_o__) reason.” —Jack Handey |
Ben Finney

[Terry Reedy]

Re: Is it allowed to use function results as default arguments ?



fred.haab wrote:

Well, others have answered the question, but I thought I'd throw in
that it would be more pythonic to do something like:
>
def Get_Relative_Pa th(target, base = None):
if base is None:
base = os.curdir
...

Since os.curdir is a constant, this is nonesensical. One only needs the
dummy default when one wants an expression re-evaluated with each call.