Make Parameterized.initialized private

[maximlt]

I think this one slipped through the cracks until now, but it was noted in the Param 2.0 plan that it should be made private #543

[maximlt]

Hmm that's why I don't like so much internal attributes on a Parameterized class, they can easily clash with user code:

• https://github.com/holoviz/panel/blob/e93b963751cf3ca1219fcfcfc66461047a3f842e/panel/pane/holoviews.py#L108
• https://github.com/holoviz/lumen/blob/7f4d22a2b47ec6ea2209bc90a915398786a00e72/lumen/views/base.py#L135
• https://github.com/holoviz-topics/EarthSim/blob/5d6bde55feaa6e95e292a90575dfc5179f5b3beb/earthsim/grabcut.py#L190

I really wonder what's the best way to avoid this kind of situation. Mangling? Relying on a private namespace a la .param?

[jlstevens]

Thanks for this!

As you know, this particular issue recently bit me.

I think both initialized and _initialized are common and likely to clash. As you say, attributes on parameterized classes often cause clashing namespaces: for this reason I suggest replace .initialized with something even less likely to be problematic e.g. _initialized_ (two underscores should do the trick!)

[hoxbro]

I agree with @jlstevens about the high likelihood of a name clash, though I would suggest __initialized instead. This is because I never really look at the end of the variable but always at the start.

[maximlt]

I agree with @jlstevens about the high likelihood of a name clash, though I would suggest __initialized instead. This is because I never really look at the end of the variable but always at the start.

The way attributes are sometimes read from an instance or from a class makes relying on mangling a little tricky, it could work though, I just need to try. Generally, I'm more in favor of looking for a way to hide all the private attributes under a private namespace, a la .param, so that we can document and protect only a few attributes.

[jlstevens]

__initialized is also fine and if there were a way to namespace the private attributes (on something double underscored) that would be even better! (Oh and yes, I do know that name mangling does make it trickier to implement)

[jbednar]

I agree with the goal of this PR, but I also agree with the observation that _initialization is also a common idiom, and so I'm not sure it's the right fix. __initialized seems fine if it can be made to work, or else putting such attributes under .param in in a very obscurely named attribute seems better.

[jlstevens]

If sticking _initialized on the param namespace object works and is easier than dealing with name mangling, I think that would be a big improvement.

[maximlt]

Superseded by #766