Variable scope and caller

[Gerhard Häring]

* Erik Lechak <elechak at bigfoot.com> [2002-12-15 13:47 -0800]:
> [...] Here is my question.  In the following code, I want to be able
> to find the value for 'y' in the function pstring.__str__.  Note that
> 'y' exists in the scope of the calling function.

> 1)  How do I find the function that called me?

This gets asked from time to time. You *can* do it if you

    envfr na rkprcgvba, gura hfr gur genpronpx zbqhyr [1]

but, as we often ask on #python, *what are you really trying to do*?

> 2)  How do I find out the local variables of a function when I am
> deeper in the stack?

As a Python programmer, you don't :-P

> 3)  How do I refer to the method testit (testit , main.testit,
> __main__.testit ...)?
> 
> class pstring:
>    data = ""
> 
>    def __init__(self, st = ""):
>       self.data = st
>       
>    def __str__(self):
>       [...]
> 
> def testit():
>    y = "erik"
>    x = pstring("hello $y")
>    print x
> 
> testit()

testit is a module-level function, so you refer to it with the name
'testit' as long as you're in the same module (no matter where there,
even deeply in a class, ...).

Gerhard

[1] If your MUA doesn't support rot13 decryption, you can enter this
into a Python prompt:

>>> u'envfr na rkprcgvba, gura hfr gur genpronpx zbqhyr'.encode('rot13')

;-)
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