List comprehension - NameError: name '_[1]' is not defined ?

[Mark Wooding]

mario ruggier <mario.ruggier at gmail.com> writes:

> 2009-01-15 22:26:18,704 ERROR [evoque] AttributeError: 'function'
> object has no attribute 'func_globals':   File "<string>", line 1, in
> <module>

Damn.  So that doesn't work. :-(

> But even if inspect did have the func_globals attribute, the "open"
> builtin will not be found on __builtins__ (that is cleaned out when
> restricted=True).

Irrelevant.  I wasn't trying to get at my __builtins__ but the one
attached to a function I was passed in, which has a different
environment.

You define a function (a method, actually, but it matters little).  The
function's globals dictionary is attached as an attribute.  You didn't
do anything special here, so the globals have the standard __builtins__
binding.  It contains open.

You now run my code in a funny environment with a stripped-down
__builtins__.  But that doesn't matter, because my environment contains
your function.  And that function has your __builtins__ hanging off the
side of it.

... but I can't actually get there because of f_restricted.  You don't
mention the fact that Python magically limits access to these attributes
if __builtins__ doesn't match the usual one, so I think you got lucky.

-- [mdw]