Mk4py - Strange Behaviour when assigning views

Hi,

Please look at the following code:

import metakit.metakit as mk

def make_view ():
        st = mk.storage()
        vw = st.getas( "test[val:I]" )
        
        for i in xrange(3): vw.append( val=i )

        print 'inside make_view():'
        print '   view obj: ', vw
        print '   structure: ', vw.structure()
        for row in vw: print '   row.val= ', row.val
        return vw

def test1 ():
        v2 = make_view()
        print 'outside make_view()'
        print '   view obj: ', v2
        print '   structure: ', v2.structure()
        for row in v2: print '   row.val= ', row.val

if __name__ == '__main__':
        print 'metakit version ', mk.version
        test1()


When running the code, I got the following output & error:
        
metakit version  2.4.9.3
inside make_view():
   view obj:  <PyView object at 8f95c0>
   structure:  [Property('I', 'val')]
   row.val=  0
   row.val=  1
   row.val=  2
outside make_view()
   view obj:  <PyView object at 8f95c0>
   structure:  []
   row.val= 
Traceback (most recent call last):
  File "test2.py", line 48, in ?
    test1()
  File "test2.py", line 21, in test1
    for row in v2: print '   row.val= ', row.val
AttributeError: val


A similar problem occurs when I store the view as an instance var in
an object and then access it later:


class testmk ( object ):
        def __init__ ( self ):
                st = mk.storage()
                self.vw = st.getas( "test[val:I]" )
                for i in xrange(3): self.vw.append( val=i )

        def prtvw ( self ):
                print 'tmk view obj: ', self.vw
                print 'tmk: structure: ', self.vw.structure()
                for row in self.vw: print 'tmk: row.val= ', row.val

def test_obj ():
        tmk = testmk()
        tmk.prtvw()

if __name__ == '__main__':
        print 'metakit version ', mk.version
        test_obj()


The resulting output and error are:

metakit version  2.4.9.3
tmk view obj:  <PyView object at 8df7d0>
tmk: structure:  []
tmk: row.val= 
Traceback (most recent call last):
  File "test2.py", line 69, in ?
    test_obj()
  File "test2.py", line 65, in test_obj
    tmk.prtvw()
  File "test2.py", line 61, in prtvw
    for row in self.vw: print 'tmk: row.val= ', row.val
AttributeError: val


I can circumvent this problem by manipulating the storage object
instead. Then whenever I need the view, I can just call
storage.view(...).  This seems to be OK.

Am I doing something wrong or could there be a possible bug?

I'm using Active Python v2.3.2 on Win XP.

Thanks!

-- 
Cheers,
choppystride


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