[Python-Dev] Subclassing varying length types (What's a PyStructSequence ?)

[Tim Peters]

[MAL]
> Perhaps we should start thinking about optimizing at least
> one of the Unicode malloc away in Python 2.3: the Unicode
> object itself can well be kept on a free list with the
> Py_UNICODE buffer freed and set to NULL. Doesn't save any memory
> but would improve the performance.

pymalloc would improve both, so I'd much rather pursue that in 2.3 than yet
another type-specific free list.

> BTW, is the memory burden really such a big argument these days ?
> I can imagine this being an argument on resource restrained
> platforms such as Palms (thanks to Martin, the Plam guys can now
> switch off Unicode completely), but hardly on gigabyte machines
> with access 100s of GBs swap-space :-)

Most of us have machines between those extremes, and the difference between
100MB and 300MB can be make-or-break.  I don't see that any "flexibility" is
gained merely by wasting memory <wink>.

> ...
> Any idea how we could make subclassing these types less
> hackish, then ?

Subclassing seems easy enough to me from the Python level; I don't have time
to revisit C-level subclasssing here (and I don't know that it's hackish
there either, but do think it's in need of docs).