Source Code for Module rospy.impl.validators

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34   
35  """Internal-use Python decorators for parameter validation""" 
36   
37 -class ParameterInvalid(Exception): 
38      """Exception that is raised when a parameter fails validation checks""" 
39 -    def __init__(self, message): 
40          self._message = message 
41   
42 -    def __str__(self): 
43          return str(self._message) 
44   
45 -def non_empty(param_name): 
46      """Validator that checks that parameter is not empty""" 
47      def validator(param, context): 
48          if not param: 
49              raise ParameterInvalid("ERROR: parameter [%s] must be specified and non-empty"%param_name) 
50          return param 
51      return validator 
52