wxPython/wx/py/pseudo.py

   1 """Provides a variety of classes to create pseudo keywords and pseudo files."""
   2
   3 __author__ = "Patrick K. O'Brien <pobrien@orbtech.com>"
   4 __cvsid__ = "$Id$"
   5 __revision__ = "$Revision$"[11:-2]
   6
   7 try:
   8     True
   9 except NameError:
  10     True = 1==1
  11     False = 1==0
  12
  13
  14 class PseudoKeyword:
  15     """A callable class that calls a method passed as a parameter.
  16
  17     Good for creating a pseudo keyword in the python runtime
  18     environment. The keyword is really an object that has a repr()
  19     that calls itself which calls the method that was passed in the
  20     init of the object. All this just to avoid having to type in the
  21     closing parens on a method. So, for example:
  22
  23         >>> quit = PseudoKeyword(SomeObject.someMethod)
  24         >>> quit
  25
  26     SomeObject.someMethod gets executed as if it had been called
  27     directly and the user didn't have to type the parens, like
  28     'quit()'. This technique is most applicable for pseudo keywords
  29     like quit, exit and help.
  30
  31     If SomeObject.someMethod can take parameters, they can still be
  32     passed by using the keyword in the traditional way with parens."""
  33
  34     def __init__(self, method):
  35         """Create a callable object that executes method when called."""
  36
  37         if callable(method):
  38             self.method = method
  39         else:
  40             raise ValueError, 'method must be callable'
  41
  42     def __call__(self, *args, **kwds):
  43         self.method(*args, **kwds)
  44
  45     def __repr__(self):
  46         self()
  47         return ''
  48
  49
  50 class PseudoFile:
  51
  52     def __init__(self):
  53         """Create a file-like object."""
  54         pass
  55
  56     def readline(self):
  57         pass
  58
  59     def write(self, s):
  60         pass
  61
  62     def writelines(self, l):
  63         map(self.write, l)
  64
  65     def flush(self):
  66         pass
  67
  68     def isatty(self):
  69         pass
  70
  71
  72 class PseudoFileIn(PseudoFile):
  73
  74     def __init__(self, readline, readlines=None):
  75         if callable(readline):
  76             self.readline = readline
  77         else:
  78             raise ValueError, 'readline must be callable'
  79         if callable(readlines):
  80             self.readlines = readlines
  81
  82     def isatty(self):
  83         return 1
  84
  85
  86 class PseudoFileOut(PseudoFile):
  87
  88     def __init__(self, write):
  89         if callable(write):
  90             self.write = write
  91         else:
  92             raise ValueError, 'write must be callable'
  93
  94     def isatty(self):
  95         return 1
  96
  97
  98 class PseudoFileErr(PseudoFile):
  99
 100     def __init__(self, write):
 101         if callable(write):
 102             self.write = write
 103         else:
 104             raise ValueError, 'write must be callable'
 105
 106     def isatty(self):
 107         return 1