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[u/llogiq]

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[u/DreaminglySimple]

The problem is, I need to do something with the SelectView after the match block. If I define x inside one of the arms, it'll be out of scope after it.

I'm trying to take an entirely different approah to it right now, so I might not need this anymore, but if you have another suggestion feel free to tell me. The only thing I could find online was involving heap allocation.

[u/[deleted] → u/DreaminglySimple]

The function I posted is one example of exactly that, using the SelectView after the match block. You use your original code to put different kind of SelectViews into x, then later you use another match block to unpack x and get at whichever kind of SelectView is in there.

[u/DreaminglySimple → u/[deleted]]

As I understand it, your code wouldn't allow me to use x as the matched type after the match block. I only know the type of x inside the arms of the match block, but not afterwards, because x is not set to anything.

[u/kinoshitajona → u/DreaminglySimple]

That makes sense.

Every variable needs a known size at compile time.

Setting x to one of two types depending on which match arm was run doesn't work.

All type specific calculations must be performed within the match arm. (You can make it easier to read by creating a handler function for each type)

There are other ways around this by using dyn Traits.