Lib/lib-old/dump.py

   1 # Module 'dump'
   2 #
   3 # Print python code that reconstructs a variable.
   4 # This only works in certain cases.
   5 #
   6 # It works fine for:
   7 # - ints and floats (except NaNs and other weird things)
   8 # - strings
   9 # - compounds and lists, provided it works for all their elements
  10 # - imported modules, provided their name is the module name
  11 #
  12 # It works for top-level dictionaries but not for dictionaries
  13 # contained in other objects (could be made to work with some hassle
  14 # though).
  15 #
  16 # It does not work for functions (all sorts), classes, class objects,
  17 # windows, files etc.
  18 #
  19 # Finally, objects referenced by more than one name or contained in more
  20 # than one other object lose their sharing property (this is bad for
  21 # strings used as exception identifiers, for instance).
  22
  23 # Dump a whole symbol table
  24 #
  25 def dumpsymtab(dict):
  26         for key in dict.keys():
  27                 dumpvar(key, dict[key])
  28
  29 # Dump a single variable
  30 #
  31 def dumpvar(name, x):
  32         import sys
  33         t = type(x)
  34         if t == type({}):
  35                 print name, '= {}'
  36                 for key in x.keys():
  37                         item = x[key]
  38                         if not printable(item):
  39                                 print '#',
  40                         print name, '[', `key`, '] =', `item`
  41         elif t in (type(''), type(0), type(0.0), type([]), type(())):
  42                 if not printable(x):
  43                         print '#',
  44                 print name, '=', `x`
  45         elif t == type(sys):
  46                 print 'import', name, '#', x
  47         else:
  48                 print '#', name, '=', x
  49
  50 # check if a value is printable in a way that can be read back with input()
  51 #
  52 def printable(x):
  53         t = type(x)
  54         if t in (type(''), type(0), type(0.0)):
  55                 return 1
  56         if t in (type([]), type(())):
  57                 for item in x:
  58                         if not printable(item):
  59                                 return 0
  60                 return 1
  61         if x == {}:
  62                 return 1
  63         return 0