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pythonreflectionnested-function

Python: access nested functions by name

Inside a function, I can use dir() to get a list of nested functions:

>>> def outer():
...  def inner(): pass
...  print dir()
...
>>> outer()
['inner']

...but then what? How can I access these functions by name? I see no __dict__ attribute.

Solution

  • First: Are you sure you want to do this? It's usually not a good idea. That said,

    def outer():
    def inner(): pass
    locals()['inner']()

    You can use locals to get a dictionary of local variable values, then look up the value of 'inner' to get the function. Don't try to edit the local variable dict, though; it won't work right.

    If you want to access the inner function outside the outer function, you'll need to store it somehow. Local variables don't become function attributes or anything like that; they're discarded when the function exits. You can return the function:

    def outer():
    def inner(): pass
    return inner

nested_func = outer()
nested_func()