On Fri, 17 Apr 2009 14:49:37 -0400, Yigal Chripun <yigal...@gmail.com>
wrote:
On 17/04/2009 21:34, bearophile wrote:
Nick Sabalausky:
There are people who swear by the ability of adding methods at
runtime and changing the inheritance hierarchy dynamically. It
makes for a very fluid environment.
Personally, I've always seen that as extremely sloppy and
haphazard.
Adding methods at runtime is named "monkey patching", and it is
considered a bad practice even in Python. In Ruby it is more common.
Usually in such languages such things are less dangerous because the
code contains lot of tests anyway. Some people say that a way to
remove most of the downsides of monkey patching is to make it scoped,
that is the changes (like a method added or replaced) to a class
aren't seen globally in the whole program (like from other modules),
but only in the scope where such change is done (and its subscopes).
I think I have not seen languages where this is doable yet.
Bye, bearophile
just like anything in life this can be overused. This is a very useful
tool in a programmer's toolbox for when you need, for example, to
quickly experiment with something or do an urgent fix.
It's like when you build a house you have it properly designed and have
solid foundations but after the house is built you can still redesign
internally without rebuilding the entire house.
It's more like adding another outside door. Try doing that ;) (BTW,
removing one is easy, but that kind of doesn't apply here...)
changing internals in code is easy, that's why we use OOP. Changing APIs
is not.
-Steve
