Here are a few python tricks

* Eliminate tail recursion *

Formerly at 
<TT>
http://mail.python.org/pipermail/python-list/2002-June/107487.html<BR>
</TT>

=>
import types

TRE_magic = "TRE magic string"

def TREcont(fn, *rest): 
        def fncont(*rest): 
            return fn(cont=TREcont, *rest)
        return (TRE_magic, fncont, rest)

def TRE(fn, *rest):
        x = fn(cont=TREcont, *rest)
        while isinstance(x, types.TupleType) and (x[0] is TRE_magic):
          x = x[1](*x[2])
        return x

def factorial(n,acc=1,cont=TRE):
        if n <= 1: return acc
        else:      return cont(factorial,n-1,acc*n)
<=

* Interactive help *

=>
>>> dir()
>>> dir('__builtins__')
>>> help()
help> keywords
help> modules
<=

* List all keywords *

=>
import keyword; print keyword.kwlist
<=


(2002-2005)