Dan Stromberg: >Rene Pijlman: >> Right. My second attempt would be: a BTree with the word as key, and a >> BTree of filenames as value
>Would ZODB let me do that? Yes. >I'm puzzled, because: >>>> d1={} >>>> d={} >>>> d[d1] = '' >TypeError: dict objects are unhashable This is using a dict as _key_, whereas I suggested to use a BTree as _value_. >I don't know how to do a btree of btrees in python... Read this first: http://www.zope.org/Wikis/ZODB/guide/node6.html#SECTION000630000000000000000 On second thought, a BTree of TreeSet's may be a better idea. The key of your outer BTree is a word. It's value is a TreeSet. The key of that TreeSet is a filename. It has no values. This provides you with a persistent scalable mapping: word -> set of filenames I estimate it takes 2 hours to learn ZODB, and 20 minutes to program a benchmark. The hours are reusable :-) -- René Pijlman -- http://mail.python.org/mailman/listinfo/python-list