inspect.getargspec(print) fails

[ubershmekel]

BPO	6905
Nosy	@birkenfeld

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2009-09-14.09:44:46.575>
created_at = <Date 2009-09-14.03:54:50.034>
labels = ['type-bug', 'library']
title = 'inspect.getargspec(print) fails'
updated_at = <Date 2009-09-18.09:14:58.938>
user = 'https://bugs.python.org/ubershmekel'

bugs.python.org fields:

activity = <Date 2009-09-18.09:14:58.938>
actor = 'georg.brandl'
assignee = 'none'
closed = True
closed_date = <Date 2009-09-14.09:44:46.575>
closer = 'georg.brandl'
components = ['Library (Lib)']
creation = <Date 2009-09-14.03:54:50.034>
creator = 'ubershmekel'
dependencies = []
files = []
hgrepos = []
issue_num = 6905
keywords = []
message_count = 4.0
messages = ['92591', '92595', '92734', '92819']
nosy_count = 2.0
nosy_names = ['georg.brandl', 'ubershmekel']
pr_nums = []
priority = 'normal'
resolution = 'wont fix'
stage = None
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue6905'
versions = ['Python 3.1']

[ubershmekel]

>>> import inspect
>>> inspect.getargspec(print)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "F:\Python31\lib\inspect.py", line 787, in getargspec
    getfullargspec(func)
  File "F:\Python31\lib\inspect.py", line 814, in getfullargspec
    raise TypeError('arg is not a Python function')
TypeError: arg is not a Python function

Is this normal or a known issue? I couldn't find an existing ticket.

[birkenfeld]

This is not an issue, but a fundamental restriction of what getargspec()
can do. C function signatures are not introspectable, because basically
every C function can be thought of as defined as either

  def func(*args)

or

  def func(*args, **kwargs)

and is free to do what it wants with the args and kwargs.

[ubershmekel]

You're right, I was confused by the statement "arg is not a Python
function". I didn't realize 'arg' meant the function I passed to
getargspec, I thought it was just strange.

After digging a bit into inspect.py, may I suggest line 814 be changed
from:
raise TypeError('arg is not a Python function')

to:
raise TypeError('%s is not a Python function' % func)

That way the error I would have received would have given:
TypeError: <built-in function print> is not a Python function

[birkenfeld]

OK, that is reasonable. I changed this and several other same-style
errors in r74901.