Tools/framer/example.py

   1 """Generate the skeleton for cStringIO as an example of framer."""
   2
   3 from framer.bases import Module, Type
   4 from framer.member import member
   5
   6 class cStringIO(Module):
   7     """A simple fast partial StringIO replacement.
   8
   9     This module provides a simple useful replacement for the StringIO
  10     module that is written in C.  It does not provide the full
  11     generality of StringIO, but it provides enough for most
  12     applications and is especially useful in conjunction with the
  13     pickle module.
  14
  15     Usage:
  16
  17     from cStringIO import StringIO
  18
  19     an_output_stream = StringIO()
  20     an_output_stream.write(some_stuff)
  21     ...
  22     value = an_output_stream.getvalue()
  23
  24     an_input_stream = StringIO(a_string)
  25     spam = an_input_stream.readline()
  26     spam = an_input_stream.read(5)
  27     an_input_stream.seek(0)             # OK, start over
  28     spam = an_input_stream.read()       # and read it all
  29     """
  30
  31     __file__ = "cStringIO.c"
  32
  33     def StringIO(o):
  34         """Return a StringIO-like stream for reading or writing"""
  35     StringIO.pyarg = "|O"
  36
  37     class InputType(Type):
  38         "Simple type for treating strings as input file streams"
  39
  40         abbrev = "input"
  41
  42         struct = """\
  43         typedef struct {
  44                 PyObject_HEAD
  45                 char *buf;
  46                 int pos;
  47                 int size;
  48                 PyObject *pbuf;
  49         } InputObject;
  50         """
  51
  52         def flush(self):
  53             """Does nothing"""
  54
  55         def getvalue(self):
  56             """Get the string value.
  57
  58             If use_pos is specified and is a true value, then the
  59             string returned will include only the text up to the
  60             current file position.
  61             """
  62
  63         def isatty(self):
  64             """Always returns False"""
  65
  66         def read(self, s):
  67             """Return s characters or the rest of the string."""
  68         read.pyarg = "|i"
  69
  70         def readline(self):
  71             """Read one line."""
  72
  73         def readlines(self, hint):
  74             """Read all lines."""
  75         readlines.pyarg = "|i"
  76
  77         def reset(self):
  78             """Reset the file position to the beginning."""
  79
  80         def tell(self):
  81             """Get the current position."""
  82
  83         def truncate(self, pos):
  84             """Truncate the file at the current position."""
  85         truncate.pyarg = "|i"
  86
  87         def seek(self, position, mode=0):
  88             """Set the current position.
  89
  90             The optional mode argument can be 0 for absolute, 1 for relative,
  91             and 2 for relative to EOF.  The default is absolute.
  92             """
  93         seek.pyarg = "i|i"
  94
  95         def close(self):
  96             pass
  97
  98     class OutputType(InputType):
  99         "Simple type for output strings."
 100
 101         abbrev = "output"
 102
 103         struct = """\
 104         typedef struct {
 105                 PyObject_HEAD
 106                 char *buf;
 107                 int pos;
 108                 int size;
 109                 int softspace;
 110         } OutputObject;
 111         """
 112
 113         softspace = member()
 114
 115         def close(self):
 116             """Explicitly release resources."""
 117
 118         def write(self, s):
 119             """Write a string to the file."""
 120             # XXX Hack: writing None resets the buffer
 121
 122         def writelines(self, lines):
 123             """Write each string in lines."""
 124
 125
 126 cStringIO.gen()
 127