[Tutor] How to use introspection to discover parameters?

[David]

On 27/07/2012, Jerry Hill <malaclypse2 at gmail.com> wrote:
...
>>>> inspect.getargspec(logging.log)
> ArgSpec(args=['level', 'msg'], varargs='args', keywords='kwargs',
> defaults=None)
...
> Also, the help object itself is written in python.  You can look at
> the source in pydoc.py

On 27/07/2012, Steven D'Aprano <steve at pearwood.info> wrote:
>
> find out what they are and what they can do. Python has a couple of built-in
> functions for introspection, plus an entire module of extra functions.
> Built-ins include: dir, vars, globals, locals, hasattr, type, help
...
> Plus the inspect module, which contains many other advanced introspection
...
> This is where it is added to the built-ins:
...
> And this is where the actual help functionality is made:
...
> 1) Source code is not always available. Even when available, it can
...
> 2) Even when you have the source code to read, reading the source can be
...
> 3) Even if the source code is short and sweet and easy to understand, this
...

Thanks for the great and comprehensive answers! I understand much better it now.
When I saw that help() was a builtin, I assumed it was written in C. So it
helped that you pointed me to pydoc and inspect.
In pydoc I found this:

        if inspect.isfunction(object):
            args, varargs, varkw, defaults = inspect.getargspec(object)

I didn't realise that so much of a "builtin" help() would be visible to me
in *.py files. I naively assumed "builtin" meant compiled-from-C.

> You might consider putting in a request for a documentation
> change on the bug tracker.

Will do.

Assistance much appreciated!