c[:]()
Erik Max Francis
max at alcyone.com
Thu May 31 19:53:05 EDT 2007
Warren Stringer wrote:
> I'm still a bit new at this, was wondering why c[:]() doesn't work, and
> implicitly wondering why it *shouldn't* work.
It does work. It means "make a sliced copy of `c`, and then call it
with no arguments." Functionally that is _no different_ from `c()`,
which means "take `c` and call it with no arguments," because presuming
`c` is a list, `c[:]` makes a shallow copy.
So if you think `c()` and `c[:]()` should do something different in this
case, you are profoundly confused about Python's semantics of what
objects are, what it means to shallow copy a list, and what it means to
make a function call. That you keep including the slice suggests that
there's something about its meaning that's not yet clicking.
If you really want syntax where a function call on a container calls all
of its elements, then that is trivially easy to do by creating such an
object and overriding its `__call__` method.
If you're not willing to do that, but still insisting that `c[:]()`
makes sense, then perhaps it would be more advisable to learn more about
Python rather than try to suggest profound changes to the language and
its conventions.
--
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
The quality, not the longevity, of one's life is what is important.
-- Dr. Martin Luther King, Jr.
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