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  • Committer: John Arbash Meinel
  • Date: 2009-05-01 20:20:37 UTC
  • mto: This revision was merged to the branch mainline in revision 4323.
  • Revision ID: john@arbash-meinel.com-20090501202037-frhn2e9060142ldf
Small tweaks from Ian.

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Lines of Context:
bzrlib/lru_cache.py
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        if self.prev is None:
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            prev_key = None
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        else:
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            prev_key = self.prev_key
 
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            prev_key = self.prev.key
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        return '%s(%r n:%r p:%r)' % (self.__class__.__name__, self.key,
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                                     self.next_key, prev_key)
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        # The "HEAD" of the lru linked list
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        self._most_recently_used = None
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        # The "TAIL" of the lru linked list
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        self._last_recently_used = None
 
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        self._least_recently_used = None
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        self._update_max_cache(max_cache, after_cleanup_count)
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    def __contains__(self, key):
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        node_prev = node.prev
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        next_key = node.next_key
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        # benchmarking shows that the lookup of _null_key in globals is faster
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        # than the attribute lookup for (node is self._last_recently_used)
 
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        # than the attribute lookup for (node is self._least_recently_used)
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        if next_key is _null_key:
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            # 'node' is the _last_recently_used, because it doesn't have a
 
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            # 'node' is the _least_recently_used, because it doesn't have a
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            # 'next' item. So move the current lru to the previous node.
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            self._last_recently_used = node_prev
 
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            self._least_recently_used = node_prev
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        else:
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            node_next = cache[next_key]
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            node_next.prev = node_prev
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                                     ' %s' % (node,))
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        while node is not None:
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            if node.next_key is _null_key:
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                if node is not self._last_recently_used:
 
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                if node is not self._least_recently_used:
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                    raise AssertionError('only the last node should have'
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                                         ' no next value: %s' % (node,))
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                node_next = None
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        # Move 'node' to the front of the queue
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        if self._most_recently_used is None:
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            self._most_recently_used = node
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            self._last_recently_used = node
 
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            self._least_recently_used = node
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            return
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        elif node is self._most_recently_used:
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            # Nothing to do, this node is already at the head of the queue
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        # We've taken care of the tail pointer, remove the node, and insert it
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        # at the front
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        # REMOVE
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        if node is self._last_recently_used:
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            self._last_recently_used = node.prev
 
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        if node is self._least_recently_used:
 
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            self._least_recently_used = node.prev
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        if node.prev is not None:
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            node.prev.next_key = node.next_key
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        if node.next_key is not _null_key:
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        node.prev = None
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    def _remove_node(self, node):
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        if node is self._last_recently_used:
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            self._last_recently_used = node.prev
 
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        if node is self._least_recently_used:
 
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            self._least_recently_used = node.prev
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        self._cache.pop(node.key)
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        # If we have removed all entries, remove the head pointer as well
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        if self._last_recently_used is None:
 
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        if self._least_recently_used is None:
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            self._most_recently_used = None
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        node.run_cleanup()
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        # Now remove this node from the linked list
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        If there are no more references to the lru, then this entry should be
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        removed from the cache.
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        """
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        self._remove_node(self._last_recently_used)
 
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        self._remove_node(self._least_recently_used)
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    def clear(self):
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        """Clear out all of the cache."""