I'm trying to make a function that will test if a function exists or not, and then return a boolean value based on if it exists or not.
Here's my code; however, Python IDLE 3.5 tells me that there is an error with my eval() statement, but I don't see what's wrong:
def testFunction(entity):
try eval(entity)():
return True
except NameError:
return False
Can someone help?
Your try statement is wrong. It should have been -
def testFunction(entity):
try: return callable(eval(entity))
except NameError:
return False
You don't need to call the function either (to check whether its available or not). The above uses the built-in function callable , to check whether the entity is a function/class or so.
But If you are checking for simple functions (and not builtin functions or module functions like module.function) I would say it would be better to use globals() dictionary and search in it, rather than using eval() . Example -
def testFunction(entity):
try: return callable(globals()[entity])
except KeyError:
return False
Please note, the above would not return True for builtin functions , or functions that you access like - module.function, etc. If you would need to test for those as well, and if you trust the source from where you get entity , you can fallback to using eval .