Lib/repr.py

   1 """Redo the `...` (representation) but with limits on most sizes."""
   2
   3 __all__ = ["Repr","repr"]
   4
   5 import sys
   6
   7 class Repr:
   8     def __init__(self):
   9         self.maxlevel = 6
  10         self.maxtuple = 6
  11         self.maxlist = 6
  12         self.maxarray = 5
  13         self.maxdict = 4
  14         self.maxstring = 30
  15         self.maxlong = 40
  16         self.maxother = 20
  17     def repr(self, x):
  18         return self.repr1(x, self.maxlevel)
  19     def repr1(self, x, level):
  20         typename = type(x).__name__
  21         if ' ' in typename:
  22             parts = typename.split()
  23             typename = '_'.join(parts)
  24         if hasattr(self, 'repr_' + typename):
  25             return getattr(self, 'repr_' + typename)(x, level)
  26         else:
  27             s = `x`
  28             if len(s) > self.maxother:
  29                 i = max(0, (self.maxother-3)//2)
  30                 j = max(0, self.maxother-3-i)
  31                 s = s[:i] + '...' + s[len(s)-j:]
  32             return s
  33     def repr_tuple(self, x, level):
  34         n = len(x)
  35         if n == 0: return '()'
  36         if level <= 0: return '(...)'
  37         s = ''
  38         for i in range(min(n, self.maxtuple)):
  39             if s: s = s + ', '
  40             s = s + self.repr1(x[i], level-1)
  41         if n > self.maxtuple: s = s + ', ...'
  42         elif n == 1: s = s + ','
  43         return '(' + s + ')'
  44     def repr_list(self, x, level):
  45         n = len(x)
  46         if n == 0: return '[]'
  47         if level <= 0: return '[...]'
  48         s = ''
  49         for i in range(min(n, self.maxlist)):
  50             if s: s = s + ', '
  51             s = s + self.repr1(x[i], level-1)
  52         if n > self.maxlist: s = s + ', ...'
  53         return '[' + s + ']'
  54
  55     def repr_array(self, x, level):
  56         n = len(x)
  57         header = "array('%s', [" % x.typecode
  58         if n == 0:
  59             return header + "])"
  60         if level <= 0:
  61             return header + "...])"
  62         s = ''
  63         for i in range(min(n, self.maxarray)):
  64             if s:
  65                 s += ', '
  66             s += self.repr1(x[i], level-1)
  67         if n > self.maxarray:
  68             s += ', ...'
  69         return header + s + "])"
  70
  71     def repr_dict(self, x, level):
  72         n = len(x)
  73         if n == 0: return '{}'
  74         if level <= 0: return '{...}'
  75         s = ''
  76         keys = x.keys()
  77         keys.sort()
  78         for i in range(min(n, self.maxdict)):
  79             if s: s = s + ', '
  80             key = keys[i]
  81             s = s + self.repr1(key, level-1)
  82             s = s + ': ' + self.repr1(x[key], level-1)
  83         if n > self.maxdict: s = s + ', ...'
  84         return '{' + s + '}'
  85     def repr_str(self, x, level):
  86         s = `x[:self.maxstring]`
  87         if len(s) > self.maxstring:
  88             i = max(0, (self.maxstring-3)//2)
  89             j = max(0, self.maxstring-3-i)
  90             s = `x[:i] + x[len(x)-j:]`
  91             s = s[:i] + '...' + s[len(s)-j:]
  92         return s
  93     def repr_long(self, x, level):
  94         s = `x` # XXX Hope this isn't too slow...
  95         if len(s) > self.maxlong:
  96             i = max(0, (self.maxlong-3)//2)
  97             j = max(0, self.maxlong-3-i)
  98             s = s[:i] + '...' + s[len(s)-j:]
  99         return s
 100     def repr_instance(self, x, level):
 101         try:
 102             s = `x`
 103             # Bugs in x.__repr__() can cause arbitrary
 104             # exceptions -- then make up something
 105         except:
 106             # On some systems (RH10) id() can be a negative number.
 107             # work around this.
 108             MAX = 2L*sys.maxint+1
 109             return '<' + x.__class__.__name__ + ' instance at %x>'%(id(x)&MAX)
 110         if len(s) > self.maxstring:
 111             i = max(0, (self.maxstring-3)//2)
 112             j = max(0, self.maxstring-3-i)
 113             s = s[:i] + '...' + s[len(s)-j:]
 114         return s
 115
 116 aRepr = Repr()
 117 repr = aRepr.repr