Good hearing from you John.
It's interesting to compare globals( ) with dir( ). That latter is affected
by
the new names in a for loop but doesn't reflect these changes until
later, whereas globals( ) raises an exception.
The globals dict seems an unusual beast. Interesting recursivity too.
>>> g = globals()
>>> g['g']['g']['g']['g']['g']['g']['g']['g']['g']
{'__builtins__': <module 'builtins' (built-in)>, '__name__': '__main__',
'__doc__': None, 'g': {...}, '__package__': None}
I call it "flat recursivity" in that we're not looking at successive frames
on some stack.
Hmmm, just stumbled upon (is "recursivity" a word?):
http://recursed.blogspot.com/
Kirby
>>> ================================ RESTART
================================
>>> g = dict(globals())
>>> g
{'__builtins__': <module 'builtins' (built-in)>, '__name__': '__main__',
'__doc__': None, '__package__': None}
>>> for t,v in g.items(): print(t,v)
__builtins__ <module 'builtins' (built-in)>
__name__ __main__
__doc__ None
__package__ None
>>> help(globals)
Help on built-in function globals in module builtins:
globals(...)
globals() -> dictionary
Return the dictionary containing the current scope's global variables.
>>> d = dir()
>>> for v in d: print(v)
__builtins__
__doc__
__name__
__package__
g
t
v
>>> ================================ RESTART
================================
>>> d = dir()
>>> for v in d: print(v)
__builtins__
__doc__
__name__
__package__
>>> g = globals()
>>> for v in g: print(v)
d
g
__builtins__
__package__
v
__name__
__doc__
>>> ================================ RESTART
================================
>>> g = globals()
>>> for v in g: print(v)
__builtins__
Traceback (most recent call last):
File "<pyshell#178>", line 1, in <module>
for v in g: print(v)
RuntimeError: dictionary changed size during iteration
>>> dir()
['__builtins__', '__doc__', '__name__', '__package__', 'g', 'v']
>>> ================================ RESTART
================================
>>> d = dir()
>>> for v in d: print(v)
__builtins__
__doc__
__name__
__package__
>>> dir()
['__builtins__', '__doc__', '__name__', '__package__', 'd', 'v']
>>>
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