"""Class based built-in exception hierarchy. This is a new feature whereby all the standard built-in exceptions, traditionally string objects, are replaced with classes. This gives Python's exception handling mechanism a more object-oriented feel. Most existing code should continue to work with class based exceptions. Some tricky uses of IOError may break, but the most common uses should work. To disable this feature, start the Python executable with the -X option. Here is a rundown of the class hierarchy. You can change this by editing this file, but it isn't recommended. The classes with a `*' are new with this feature. They are defined as tuples containing the derived exceptions when string-based exceptions are used. Exception(*) | +-- StandardError(*) | +-- SystemExit +-- KeyboardInterrupt +-- ImportError +-- IOError +-- EOFError +-- RuntimeError +-- NameError +-- AttributeError +-- SyntaxError +-- TypeError +-- AssertionError +-- LookupError(*) | | | +-- IndexError | +-- KeyError | +-- ArithmeticError(*) | | | +-- OverflowError | +-- ZeroDivisionError | +-- FloatingPointError | +-- ValueError +-- SystemError +-- MemoryError """ class Exception: def __init__(self, *args): self.args = args def __str__(self): if not self.args: return '' elif len(self.args) == 1: return str(self.args[0]) else: return str(self.args) def __getitem__(self, i): return self.args[i] class StandardError(Exception): pass class SyntaxError(StandardError): filename = lineno = offset = text = None msg = "" def __init__(self, *args): self.args = args if len(self.args) >= 1: self.msg = self.args[0] if len(self.args) == 2: info = self.args[1] try: self.filename, self.lineno, self.offset, self.text = info except: pass def __str__(self): return str(self.msg) class IOError(StandardError): def __init__(self, *args): self.args = args self.errno = None self.strerror = None if len(args) == 2: # common case: PyErr_SetFromErrno() self.errno = args[0] self.strerror = args[1] class RuntimeError(StandardError): pass class SystemError(StandardError): pass class EOFError(StandardError): pass class ImportError(StandardError): pass class TypeError(StandardError): pass class ValueError(StandardError): pass class KeyboardInterrupt(StandardError): pass class AssertionError(StandardError): pass class ArithmeticError(StandardError): pass class OverflowError(ArithmeticError): pass class FloatingPointError(ArithmeticError): pass class ZeroDivisionError(ArithmeticError): pass class LookupError(StandardError): pass class IndexError(LookupError): pass class KeyError(LookupError): pass class AttributeError(StandardError): pass class NameError(StandardError): pass class MemoryError(StandardError): pass class SystemExit(Exception): def __init__(self, *args): self.args = args if len(args) == 0: self.code = None elif len(args) == 1: self.code = args[0] else: self.code = args