Feature request: Ability to construct `Weak<T>` from `RcBorrow<T>`

[yvt]

Currently, one has to first convert [A]rcBorrow to [A]rc before obtaining Weak. It would be great if Weak could be constructed directly without this extra step.

[CAD97]

Yeah, I agree, this is useful. #59 implements the functionality.

In retrospect, I wish downgrade returned a Weak instead of &'a T. Do you have any suggestions for what to call this function?

[yvt]

do you have any other suggestions for what this method should be called?

Sorry, I don't have any. It's really a shame that downgrade is already taken.

How do you feel about redoing the naming scheme in the next major version (0.2.x)? This would be a breaking change, but the impact of introducing breaking changes tends to accumulate as you try to defer it, which makes it important to iron out any API design issues at the earliest moment possible (this needs to be balanced against annoyance to users, though). I think this is the point of pre-1.0 versions.

[CAD97]

rc-borrow is already v1.0. All of pointer-utils is: it was important to me to signal that these utilities are "production worthy," so I published them at 1.0.

On top of this, [A]RcBorrow is a type intended to be used in public APIs. This makes breaking changes more problematic, as they necessarily cascade into people who use rc-borrow, rather than being self-contained.

The point is that rc-borrow doesn't need breaking changes, and it won't need breaking changes; the core functionality works as intended and doesn't need API-breaking changes.

It'll be sad to lose downgrade, but maybe deprecating downgrade and adding [in]to_weak and [in]to_ref wouldn't be too bad.

[yvt]

Hmm, I wonder why I thought rc-borrow was still at 0.1.x. Anyway, In that case, I agree that the ship has already sailed.

It'll be sad to lose downgrade, but maybe deprecating downgrade and adding [in]to_weak and [in]to_ref wouldn't be too bad.

Considering the circumstances, this sounds good to me, except that I feel as_ref is more appropriate according to the style guide.

[CAD97]

I just added to_weak in #59 and will hopefully publish this soon-ish. (My workspace helper is acting up right now, though, so it might be a bit.)

I'll consider renaming downgrade in the future, but to_weak is nonproblematic to add right now.

[CAD97]

Published as v1.3.0 🎉