[Python-3000] Metaclasses in Python 3000: Draft 2 (original) (raw)

Phillip J. Eby pje at telecommunity.com
Wed Mar 14 17:15:39 CET 2007

At 08:49 PM 3/14/2007 +1300, Greg Ewing wrote:

Talin wrote: > It does not need to implement the full dictionary interface; > only the ability to insert items and retrieve them are > required. (Note: double check that this is true).

Deletion ability might be required as well, in case del is used in the class body.

Right, and some weird metaclasses might only need the ability to set, or only the ability to get. (Actually, 90%+ of today's classes could get by with just setting, and no getting or deleting.)

So the subset required is determined entirely by what the class body (and metaclass new) require.

It should probably be noted that type.new is still going to want a real dictionary, which it will then proxy. So the metaclass' new is going to need to read out the contents of the pseudo-dict somehow, or generate alternative contents.

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