On 26 Mar 2005 22:51:14 -0800, [EMAIL PROTECTED] (Oren
Tirosh) wrote:
>Ron_Adam <[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED]>...
>> Is there a way to hide global names from a function or class?
>>
>> I want to be sure that a function doesn't use any global variables by
>> mistake. So hiding them would force a name error in the case that I
>> omit an initialization step. This might be a good way to quickly
>> catch some hard to find, but easy to fix, errors in large code blocks.
>
>def noglobals(f):
>. import new
>. return new.function(
>. f.func_code,
>. {'__builtins__':__builtins__},
>. f.func_name,
>. f.func_defaults,
>. f.func_closure
>. )
>
>You can use it with the Python 2.4 @decorator syntax:
>
>@noglobals
>def a(...):
>. # code here
Cool! I haven't played with decorators yet. :)
I noticed the 'new' module is depreciated. It referred me to call the
object type directly instead. So this is probably the better way.
def noglobals(f):
return type(f)(
f.func_code,
{'__builtins__':__builtins__},
f.func_name,
f.func_defaults,
f.func_closure )
@noglobals
def a():
global x
try: x
except: x=0
x += 1
return x
x = 5
for n in range(10):
print a()
print x # x is still 5
So this is another, but longer, way to do a generator.
>>> print type(a).__doc__
function(code, globals[, name[, argdefs[, closure]]])
Create a function object from a code object and a dictionary.
The optional name string overrides the name from the code object.
The optional argdefs tuple specifies the default argument values.
The optional closure tuple supplies the bindings for free variables.
>>>
What are 'free variables'?
And is there a way to directly read what names in a function are set
with the global statement? (Other than looking at the monitor. ;)
Ron_Adam
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