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- Subject: RE: finding out number of records in a table??
- From: "Paul Hudson" <phudson@...>
- Date: Wed, 13 Sep 2006 07:05:31 +0100
>True enough. :) I missed your point, but now I think the main issue here is
>that for tables, if table[key] ~= nil, key/value access metamethods
>and __newindex) are not called; this would have to change with a new
>__removeindex, and, if so, why not simply use __newindex?
Because the pre-conditions are different, which would pointlessly (in my
view) complicate the code, and metamethods should run fast.
Now, __newindex is called if and only if the key does not exist in the
__removeindex would be called if and only if the key did exist and was being
set to null.
Re-using __newindex instead would mean if the value was nil, the key was
being removed - or would it? What about an as-yet-non-existent key that was
being set to nil, and so not in fact to be added?
Adding __removeindex seems clearer and cleaner.
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