Storing nested structures in MK 2.3.2

As of the July 25 release of MK 2.3.2 beta, you can now define recursive / self-referential view structures using the subview[^] notation. There's a demo in "examples/selfref.py":

 # Demo of the new 2.3 self-referential view structures.
 #
 # Output:
 #   0
 #   00000 1
 #   11111 1
 #   22222 0
 #   [Property('S', 's'), Property('V', 'sub')]
 #   00000 1
 #   11111 1
 #   22222 0
 #   [Property('S', 's'), Property('I', 'i'), Property('V', 'sub')]
 #   ok
 import os
 try: os.remove("_selfref.mk")
 except: pass
 import metakit
 db = metakit.storage('_selfref.mk',1)
 vw = db.getas('data[s:S,sub[^]]')
 print len(vw)
 v = vw
 for i in range(3):
     v.append(s=`i`*5)
     v = v[0].sub
 def show(vw):
     for v in [vw[0], vw[0].sub[0], vw[0].sub[0].sub[0]]:
         print v.s, len(v.sub)
     print vw[0].sub[0].sub[0].sub.structure()
     assert len(vw[0].sub[0].sub[0].sub) == 0
     try:
         metakit.dump(vw[0].sub[0].sub[0].sub[0].sub)
     except IndexError:
         pass
 show(vw)
 # note that (recursive!) on-the-fly restructuring works
 show(db.getas('data[s:S,i:I,sub[^]]'))
 db.commit()
 print 'ok'
 os.remove("_selfref.mk")

September 2001: Use http://e4graph.sourceforge.net to store your nested structures. If someone wanted to do a Python binding that would be really nice..