Håkan Persson wrote:
Hi.
I am trying to "convert" a string into a function pointer. Suppose I have the following:
from a import a from b import b from c import c
funcString = GetFunctionAsString()
and funcString is a string that contains either "a", "b" or "c".
How can I simply call the correct function?
I have tried using getattr() but I don't know what the first (object) argument should be in this case.
Thanks, Håkan Persson
Well, one really horrible way would be
getattr(sys.modules['__main__'], funcString)
and, of course, if you were going to use it a lot you could optimize slightly with
this = sys.modules['__main__']
followed later by
this = getattr(this, funcString)
Overall, however, it might be better to set uip a mapping for the functions you need to be accessible. This has the further merits that
a) You can heve different, and/or multiple names for a function
b) You can trap errors more easily
c) erm, I forgot the third advantage, consider this the Spanish
Inquisition in reverse :-)So:
funcMap = {
"a": a,
"A": a,
"b": b,
"exoticName": c }...
funcString = GetFunctionAsString()
try:
f = funcMap(funcString)
except KeyError:
print "No such function"
raise SomethingElse
result = f(args)regards Steve -- Meet the Python developers and your c.l.py favorites March 23-25 Come to PyCon DC 2005 http://www.pycon.org/ Steve Holden http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
