new_contents: # -*- encoding: utf-8 -*-
  #
  # Copyright P. Christeas <p_christ@hol.gr> 2008,2009
  #
  #
  # WARNING: This program as such is intended to be used by professional
  # programmers who take the whole responsability of assessing all potential
  # consequences resulting from its eventual inadequacies and bugs
  # End users who are looking for a ready-to-use solution with commercial
  # garantees and support are strongly adviced to contract a Free Software
  # Service Company
  #
  # This program is Free Software; you can redistribute it and/or
  # modify it under the terms of the GNU General Public License
  # as published by the Free Software Foundation; either version 2
  # of the License, or (at your option) any later version.
  #
  # This program is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  # GNU General Public License for more details.
  #
  # You should have received a copy of the GNU General Public License
  # along with this program; if not, write to the Free Software
  # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  ###############################################################################
  
  __export_bis = {}
  
  def __init_ebis():
  	global __export_bis
  	
  	_evars = [ 'abs', 'all', 'any', 'basestring' , 'bin', 'bool', 
  		'chr', 'cmp','complex', 'dict', 'divmod', 'enumerate',
  		'float','format', 'frozenset', 'getattr', 'hasattr', 'hash',
  		'hex', 'id','int', 'iter', 'len', 'list', 'long', 'map', 'max',
  		'min','next', 'oct', 'ord','pow', 'range', 'reduce', 'repr',
  		'reversed', 'round', 'set', 'setattr', 'slice','sorted', 'str',
  		'sum', 'tuple','type', 'unichr','unicode', 'xrange',
  		'True','False', 'None', 'NotImplemented', 'Ellipsis', ]
  		
  	for v in _evars:
  		__export_bis[v] = __builtins__[v]
  	
  
  __init_ebis()
  
  
  def safe_eval(expr,sglobals,slocals = None):
  	""" A little safer version of eval().
  	    This one, will use fewer builtin functions, so that only
  	    arithmetic and logic expressions can really work """
  	
  	global __export_bis
  
  	if not sglobals.has_key('__builtins__'):
  		# we copy, because we wouldn't want successive calls to safe_eval
  		# to be able to alter the builtins.
  		sglobals['__builtins__'] = __export_bis.copy()
  		
  	return eval(expr,sglobals,slocals)
  	
  #eof
subject: Implement safe_eval() in order to armour eval()