Could str () crash in Python?

Question

Are there any cases where str() throws an exception in Python?

Answer 1

Yes, it may crash for custom classes:

 >>> class C(object): ... def __str__(self): ... return 'oops: ' + oops ... >>> c = C() >>> str(c) NameError: global name 'oops' is not defined 

It may even crash for some built-in classes such as unicode :

 >>> u = u'\xff' >>> s = str(u) UnicodeEncodeError: 'ascii' codec can't encode character u'\xff' in position 0: ordinal not in range(128) 

Answer 2

Oh sure:

 class A(object): def __str__(self): raise Exception a = A() str(a) 

Answer 3

It depends on the object you are calling str() on. Each object can define its own implementation in the __str__() function, and this can easily throw an exception.

Example:

 class A: def __str__(self): raise Exception str(A())