Virtual Slicing
Bryan Olson
fakeaddress at nowhere.org
Mon Aug 29 15:55:20 EDT 2005
Sybren Stuvel wrote:
> Bryan Olson enlightened us with:
>
>>I recently wrote a module supporting value-shared slicing.
>
> Maybe I'm dumb, but could you explain this concept? Why would someone
> whant this?
My original motivation was reduce the amount of copying in some
tools that parse nested structures. All I really needed at the
time was a reference to a string, and the start and stop values.
Once I adopted Python's sequence interface, I thought I might as
well implement it consistently, generally, and completely.
So the first reason someone might want this is for efficiency,
in space and/or time.
The second reason is more abstract. Python's slice assignment is
a useful feature, but the slice selection must appear on the
right-hand-side of assignment. VSlice lets one instantiate the
updatable slice as an object, and pass it around.
I looked into supporting slice assignment between slices of
different sizes when possible, but the various options I came up
with all sucked.
--
--Bryan
More information about the Python-list
mailing list