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