#!/usr/bin/env python
     # encoding: utf-8
     #
     # Copyright (c) 2010 Doug Hellmann.  All rights reserved.
     #
     """Default handling.
     """
     #end_pymotw_header
     
     import ConfigParser
     
     # Define the names of the options
     option_names =  [
         'from-default',
         'from-section', 'section-only',
         'file-only', 'init-only', 'init-and-file',
         'from-vars',
         ]
     
     # Initialize the parser with some defaults
     parser = ConfigParser.SafeConfigParser(
         defaults={'from-default':'value from defaults passed to init',
                   'init-only':'value from defaults passed to init',
                   'init-and-file':'value from defaults passed to init',
                   'from-section':'value from defaults passed to init',
                   'from-vars':'value from defaults passed to init',
                   })
     
     print 'Defaults before loading file:'
     defaults = parser.defaults()
     for name in option_names:
         if name in defaults:
             print '  %-15s = %r' % (name, defaults[name])
     
     # Load the configuration file
     parser.read('with-defaults.ini')
     
     print '\nDefaults after loading file:'
     defaults = parser.defaults()
     for name in option_names:
         if name in defaults:
             print '  %-15s = %r' % (name, defaults[name])
     
     # Define some local overrides
     vars = {'from-vars':'value from vars'}
     
     # Show the values of all of the options
     print '\nOption lookup:'
     for name in option_names:
         value = parser.get('sect', name, vars=vars)
         print '  %-15s = %r' % (name, value)
     
     # Show error messages for options that do not exist
     print '\nError cases:'
     try:
         print 'No such option :', parser.get('sect', 'no-option')
     except ConfigParser.NoOptionError, err:
         print str(err)
     
     try:
         print 'No such section:', parser.get('no-sect', 'no-option')
     except ConfigParser.NoSectionError, err:
         print str(err)