getrecursiondepth

[Andrew Dalke]

Manlio Perillo wrote:
>>>>foo()
> 
> n = 0 and recursion depth = 1
> n = 1 and recursion depth = 2
> n = 2 and recursion depth = 3
> n = 3 and recursion depth = 4

  Why is it needed?

  Unlike getrecursionlimit it is something that can be
calculated pretty easily.

 >>> def getdepth():
...   f = sys._getframe()
...   i = -1
...   while 1:
...     try:
...       f = f.f_back
...     except AttributeError:
...       return i
...     i = i + 1
...
 >>> def test(n):
...   if n==0: return getdepth()
...   return test(n-1)
...
 >>> test(10)
12
 >>> test(30)
32
 >>> test(sys.getrecursionlimit()-3)
999
 >>>

Anything which depends on the exact number is going
to have problems because that depends on the environment.
For example, in idle getdepth() from its shell
returns 4 instead of the 2 found in the command-line
shell.

				Andrew
				dalke at dalkescientific.com