author | William Roberts <williamr@symbian.org> |
Tue, 04 Aug 2009 10:28:23 +0100 | |
changeset 2 | d55eb581a87c |
parent 1 | 2fb8b9db1c86 |
permissions | -rw-r--r-- |
1
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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1 |
"""Generic metaclass. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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Initial QEMU (symbian-qemu-0.9.1-12) import
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XXX This is very much a work in progress. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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Initial QEMU (symbian-qemu-0.9.1-12) import
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5 |
""" |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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Initial QEMU (symbian-qemu-0.9.1-12) import
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7 |
import types |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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class MetaMethodWrapper: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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10 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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11 |
def __init__(self, func, inst): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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12 |
self.func = func |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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13 |
self.inst = inst |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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14 |
self.__name__ = self.func.__name__ |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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16 |
def __call__(self, *args, **kw): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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17 |
return apply(self.func, (self.inst,) + args, kw) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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18 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
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class MetaHelper: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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20 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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21 |
__methodwrapper__ = MetaMethodWrapper # For derived helpers to override |
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|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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23 |
def __helperinit__(self, formalclass): |
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24 |
self.__formalclass__ = formalclass |
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25 |
|
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26 |
def __getattr__(self, name): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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27 |
# Invoked for any attr not in the instance's __dict__ |
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28 |
try: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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29 |
raw = self.__formalclass__.__getattr__(name) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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30 |
except AttributeError: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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31 |
try: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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32 |
ga = self.__formalclass__.__getattr__('__usergetattr__') |
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33 |
except (KeyError, AttributeError): |
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34 |
raise AttributeError, name |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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35 |
return ga(self, name) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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36 |
if type(raw) != types.FunctionType: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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37 |
return raw |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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38 |
return self.__methodwrapper__(raw, self) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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39 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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40 |
class MetaClass: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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41 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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42 |
"""A generic metaclass. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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43 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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44 |
This can be subclassed to implement various kinds of meta-behavior. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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Initial QEMU (symbian-qemu-0.9.1-12) import
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46 |
""" |
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47 |
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__helper__ = MetaHelper # For derived metaclasses to override |
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49 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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__inited = 0 |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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51 |
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52 |
def __init__(self, name, bases, dict): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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53 |
try: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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54 |
ga = dict['__getattr__'] |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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55 |
except KeyError: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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56 |
pass |
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57 |
else: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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58 |
dict['__usergetattr__'] = ga |
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59 |
del dict['__getattr__'] |
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60 |
self.__name__ = name |
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parents:
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61 |
self.__bases__ = bases |
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62 |
self.__realdict__ = dict |
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63 |
self.__inited = 1 |
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64 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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65 |
def __getattr__(self, name): |
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parents:
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66 |
try: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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67 |
return self.__realdict__[name] |
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parents:
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68 |
except KeyError: |
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parents:
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69 |
for base in self.__bases__: |
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70 |
try: |
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71 |
return base.__getattr__(name) |
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72 |
except AttributeError: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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73 |
pass |
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74 |
raise AttributeError, name |
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|
75 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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76 |
def __setattr__(self, name, value): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
77 |
if not self.__inited: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
78 |
self.__dict__[name] = value |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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79 |
else: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
80 |
self.__realdict__[name] = value |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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81 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
82 |
def __call__(self, *args, **kw): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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83 |
inst = self.__helper__() |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
84 |
inst.__helperinit__(self) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
85 |
try: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
86 |
init = inst.__getattr__('__init__') |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
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|
87 |
except AttributeError: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
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|
88 |
init = lambda: None |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
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|
89 |
apply(init, args, kw) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
90 |
return inst |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
91 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
92 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
93 |
Meta = MetaClass('Meta', (), {}) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
94 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
95 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
96 |
def _test(): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
97 |
class C(Meta): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
98 |
def __init__(self, *args): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
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|
99 |
print "__init__, args =", args |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
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|
100 |
def m1(self, x): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
101 |
print "m1(x=%r)" % (x,) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
102 |
print C |
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parents:
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|
103 |
x = C() |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
104 |
print x |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
105 |
x.m1(12) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
106 |
class D(C): |
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parents:
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|
107 |
def __getattr__(self, name): |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
108 |
if name[:2] == '__': raise AttributeError, name |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
109 |
return "getattr:%s" % name |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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|
110 |
x = D() |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
111 |
print x.foo |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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112 |
print x._foo |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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113 |
## print x.__foo |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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114 |
## print x.__foo__ |
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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changeset
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115 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
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|
116 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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117 |
if __name__ == '__main__': |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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118 |
_test() |