[Zope] odd iteration semantics in ZPT

[dman]

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On Wed, May 08, 2002 at 10:37:12PM +0200, Dieter Maurer wrote:
| dman writes:
|  > ....
|  > I managed to track it down to the fact that
|  > __getitem__ is called twice with 0 as the index.  The sequence of
|  > index values looks like :  [0, 0, 1, 2, 3, 4, 5, 6, 7, 8]
|  > I can work around this anomaly by resetting my iterator every time the
|  > index is 0.
|  >=20
|  > Is this a bug in zope?  (I expect that the bug is in ZTUtils/Iterator.=
py)
|
| I do not call this a bug, because there is not spec that forbids to
| call an index twice.

I suppose you may have a point ... the problem lies in python's
pre-iterators iteration semantics.  The __getitem__ serves as the
interface for both a random-access collection and a one-way iterator.
I expected tal:repeat to have the same semantics as python's 'for'.

At the least it should be defined that tal:repeat only works on
random-access containers and doesn't work with one-way iterators.

-D

--=20

How great is the love the Father has lavished on us,
that we should be called children of God!
        1 John 3:1=20
=20
GnuPG key : http://dman.ddts.net/~dman/public_key.gpg


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