File: //usr/lib64/python2.7/compiler/visitor.pyc
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   ASTVisitorc           B   s8   e  Z d  Z d Z d �  Z d �  Z d �  Z d �  Z RS(   s  Performs a depth-first walk of the AST
    The ASTVisitor will walk the AST, performing either a preorder or
    postorder traversal depending on which method is called.
    methods:
    preorder(tree, visitor)
    postorder(tree, visitor)
        tree: an instance of ast.Node
        visitor: an instance with visitXXX methods
    The ASTVisitor is responsible for walking over the tree in the
    correct order.  For each node, it checks the visitor argument for
    a method named 'visitNodeType' where NodeType is the name of the
    node's class, e.g. Class.  If the method exists, it is called
    with the node as its sole argument.
    The visitor method for a particular node type can control how
    child nodes are visited during a preorder walk.  (It can't control
    the order during a postorder walk, because it is called _after_
    the walk has occurred.)  The ASTVisitor modifies the visitor
    argument by adding a visit method to the visitor; this method can
    be used to visit a child node of arbitrary type.
    i    c         C   s   d  |  _ i  |  _ d  S(   N(   t   Nonet   nodet   _cache(   t   self(    (    s(   /usr/lib64/python2.7/compiler/visitor.pyt   __init__"