cpython/Lib/exceptions.py

167 lines
3.5 KiB
Python

"""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.
StandardError(*)
|
+-- SystemExit
+-- KeyboardInterrupt
+-- ImportError
+-- IOError
+-- EOFError
+-- RuntimeError
+-- NameError
+-- AttributeError
+-- SyntaxError
+-- TypeError
+-- AssertionError
+-- LookupError(*)
| |
| +-- IndexError
| +-- KeyError
|
+-- NumberError(*)
| |
| +-- OverflowError
| +-- ZeroDivisionError
| +-- FloatingPointError
|
+-- ValueError
+-- SystemError
+-- MemoryError
"""
class StandardError:
def __init__(self, *args):
if len(args) == 0:
self.args = None
elif len(args) == 1:
# de-tuplify
self.args = args[0]
else:
self.args = args
def __str__(self):
if self.args == None:
return ''
else:
return str(self.args)
def __getitem__(self, i):
if type(self.args) == type(()):
return self.args[i]
elif i == 0:
return self.args
else:
raise IndexError
class SyntaxError(StandardError):
filename = lineno = offset = text = None
def __init__(self, msg, info=None):
self.msg = msg
if info:
self.args = msg
else:
self.args = (msg, info)
if info:
self.filename, self.lineno, self.offset, self.text = info
def __str__(self):
return str(self.msg)
class IOError(StandardError):
def __init__(self, *args):
self.errno = None
self.strerror = None
if len(args) == 1:
# de-tuplify
self.args = args[0]
elif len(args) == 2:
# common case: PyErr_SetFromErrno()
self.args = args
self.errno = args[0]
self.strerror = args[1]
else:
self.args = args
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 NumberError(StandardError):
pass
class OverflowError(NumberError):
pass
class FloatingPointError(NumberError):
pass
class ZeroDivisionError(NumberError):
pass
class LookupError(StandardError):
pass
class IndexError(LookupError):
pass
class KeyError(LookupError):
pass
# debate: should these two inherit from LookupError?
class AttributeError(StandardError):
pass
class NameError(StandardError):
pass
class SystemExit(StandardError):
def __init__(self, *args):
if len(args) == 0:
self.args = None
elif len(args) == 1:
# de-tuplify
self.args = args[0]
else:
self.args = args
self.code = self.args
class MemoryError(StandardError):
pass