removed useless class

theano/sandbox/scan_module/scan_utils.py

@@ -316,77 +316,6 @@ def infer_shape(outs, inputs, input_shapes):
     return ret
 
 
-class Validator(object):
-    def __init__(self, valid=[], invalid=[], valid_equivalent={}):
-        '''
-        Check if variables can be expressed without using variables in invalid.
-
-        init_valid_equivalent provides a dictionary mapping some invalid
-        variables to valid ones that can be used instead.
-        '''
-
-        # Nodes that are valid to have in the graph computing outputs
-        self.valid = set(valid)
-
-        # Nodes that are NOT valid to have in the graph computing outputs
-        self.invalid = set(invalid)
-
-        # Mapping from invalid variables to equivalent valid ones.
-        self.valid_equivalent = valid_equivalent.copy()
-        self.valid.update(valid_equivalent.values())
-        self.invalid.update(valid_equivalent.keys())
-
-    def check(self, out):
-        '''
-        Go backwards in the graph, from out, and check if out is valid.
-
-        If out is a valid node, (out, True) is returned.
-        If out is not valid, but has an equivalent e, (e, False) is returned.
-        If out is not valid and has no equivalent, None is returned.
-        '''
-        if out in self.valid:
-            return out, True
-        elif out in self.valid_equivalent:
-            return self.valid_equivalent[out], False
-        elif out in self.invalid:
-            return None
-
-        if out.owner is None:
-            # This is an unknown input node, so it is invalid.
-            self.invalid.add(out)
-            if isinstance(out, tensor.TensorConstant):
-                # We can clone it to get a valid constant
-                cloned_out = out.clone()
-                self.valid.add(cloned_out)
-                self.valid_equivalent[out] = cloned_out
-                return cloned_out, False
-
-            return None
-
-        # Recurse over inputs
-        inputs = [self.check(i) for i in out.owner.inputs]
-
-        # If some inputs are invalid without equivalent, so is out
-        if None in inputs:
-            self.invalid.add(out)
-            return None
-
-        # If some inputs are invalid with equivalent,
-        # an equivalent out should be built and returned
-        all_inputs = [inp for (inp, is_valid) in inputs]
-        equiv_inputs = [inp for (inp, is_valid) in inputs if not is_valid]
-        if equiv_inputs:
-            cloned_node = out.owner.clone_with_new_inputs(all_inputs)
-            cloned_out = cloned_node.outputs[out.index]
-            self.invalid.add(out)
-            self.valid.add(cloned_out)
-            self.valid_equivalent[out] = cloned_out
-            return cloned_out, False
-
-        # All inputs are valid, so is out
-        return out, True
-
-
 def allocate_memory(T, y_info, y):
     """
     Allocates memory for an output of scan.