1  """Constants and membership tests for ASCII characters"""
       2  
       3  NUL     = 0x00  # ^@
       4  SOH     = 0x01  # ^A
       5  STX     = 0x02  # ^B
       6  ETX     = 0x03  # ^C
       7  EOT     = 0x04  # ^D
       8  ENQ     = 0x05  # ^E
       9  ACK     = 0x06  # ^F
      10  BEL     = 0x07  # ^G
      11  BS      = 0x08  # ^H
      12  TAB     = 0x09  # ^I
      13  HT      = 0x09  # ^I
      14  LF      = 0x0a  # ^J
      15  NL      = 0x0a  # ^J
      16  VT      = 0x0b  # ^K
      17  FF      = 0x0c  # ^L
      18  CR      = 0x0d  # ^M
      19  SO      = 0x0e  # ^N
      20  SI      = 0x0f  # ^O
      21  DLE     = 0x10  # ^P
      22  DC1     = 0x11  # ^Q
      23  DC2     = 0x12  # ^R
      24  DC3     = 0x13  # ^S
      25  DC4     = 0x14  # ^T
      26  NAK     = 0x15  # ^U
      27  SYN     = 0x16  # ^V
      28  ETB     = 0x17  # ^W
      29  CAN     = 0x18  # ^X
      30  EM      = 0x19  # ^Y
      31  SUB     = 0x1a  # ^Z
      32  ESC     = 0x1b  # ^[
      33  FS      = 0x1c  # ^\
      34  GS      = 0x1d  # ^]
      35  RS      = 0x1e  # ^^
      36  US      = 0x1f  # ^_
      37  SP      = 0x20  # space
      38  DEL     = 0x7f  # delete
      39  
      40  controlnames = [
      41  "NUL", "SOH", "STX", "ETX", "EOT", "ENQ", "ACK", "BEL",
      42  "BS",  "HT",  "LF",  "VT",  "FF",  "CR",  "SO",  "SI",
      43  "DLE", "DC1", "DC2", "DC3", "DC4", "NAK", "SYN", "ETB",
      44  "CAN", "EM",  "SUB", "ESC", "FS",  "GS",  "RS",  "US",
      45  "SP"
      46  ]
      47  
      48  def _ctoi(c):
      49      if isinstance(c, str):
      50          return ord(c)
      51      else:
      52          return c
      53  
      54  def isalnum(c): return isalpha(c) or isdigit(c)
      55  def isalpha(c): return isupper(c) or islower(c)
      56  def isascii(c): return 0 <= _ctoi(c) <= 127          # ?
      57  def isblank(c): return _ctoi(c) in (9, 32)
      58  def iscntrl(c): return 0 <= _ctoi(c) <= 31 or _ctoi(c) == 127
      59  def isdigit(c): return 48 <= _ctoi(c) <= 57
      60  def isgraph(c): return 33 <= _ctoi(c) <= 126
      61  def islower(c): return 97 <= _ctoi(c) <= 122
      62  def isprint(c): return 32 <= _ctoi(c) <= 126
      63  def ispunct(c): return isgraph(c) and not isalnum(c)
      64  def isspace(c): return _ctoi(c) in (9, 10, 11, 12, 13, 32)
      65  def isupper(c): return 65 <= _ctoi(c) <= 90
      66  def isxdigit(c): return isdigit(c) or \
      67      (65 <= _ctoi(c) <= 70) or (97 <= _ctoi(c) <= 102)
      68  def isctrl(c): return 0 <= _ctoi(c) < 32
      69  def ismeta(c): return _ctoi(c) > 127
      70  
      71  def ascii(c):
      72      if isinstance(c, str):
      73          return chr(_ctoi(c) & 0x7f)
      74      else:
      75          return _ctoi(c) & 0x7f
      76  
      77  def ctrl(c):
      78      if isinstance(c, str):
      79          return chr(_ctoi(c) & 0x1f)
      80      else:
      81          return _ctoi(c) & 0x1f
      82  
      83  def alt(c):
      84      if isinstance(c, str):
      85          return chr(_ctoi(c) | 0x80)
      86      else:
      87          return _ctoi(c) | 0x80
      88  
      89  def unctrl(c):
      90      bits = _ctoi(c)
      91      if bits == 0x7f:
      92          rep = "^?"
      93      elif isprint(bits & 0x7f):
      94          rep = chr(bits & 0x7f)
      95      else:
      96          rep = "^" + chr(((bits & 0x7f) | 0x20) + 0x20)
      97      if bits & 0x80:
      98          return "!" + rep
      99      return rep