Documentation to exec_ does not match implementation about six

[benjaminp]

Original comment by Bernhard Gschaider (Bitbucket: bgschaid, GitHub: bgschaid):

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That's fine with me. The thing was I saw the docu when porting and thought "Ah. Keyword arguments. That is self-documenting. Lets use it". And I didn't test that particular path on python3 so I didn't see the error of my ways

[benjaminp]

I hope that's good enough for you.

[benjaminp]

rename python 2's exec_ arguments to avoid accidently calling with keywords (fixes #16)

[benjaminp]

Original comment by Bernhard Gschaider (Bitbucket: bgschaid, GitHub: bgschaid):

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Right. So exec_ behaves differently on Python2 and Python3 and the point of six is to hide these differences. So what I'd propose is either

1. Write for Python3 a function that wraps exec and accepts keywords

2. Rewrite the Python2 implementation to something like (just a sketch)

#!python

def exec_(code,*args):
     globs,locs=None,None
     if len(args)>0:
        globs=args[0]
     if len(args)>1:
        locs=args[1]
     if len(args)>2:
        raise TypeError("exec expected at most 3 arguments, got 4")
    # After that the current implementation

[benjaminp]

You shouldn't rely on it, though because

#!pycon
Python 3.4.0a0 (default:ce99559efa46+, Jan  8 2013, 11:43:31) 
[GCC 4.5.4] on linux
Type "help", "copyright", "credits" or "license" for more information.
x>>> exec("x", globals={})
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: exec() takes no keyword arguments

[benjaminp]

Original comment by Bernhard Gschaider (Bitbucket: bgschaid, GitHub: bgschaid):

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Yes. I ported a piece of code that used them as named parameters and it blew up

[benjaminp]

I assume the difference you're referring to is the argument names?