Define Tuple type

[kmoe]

Implementation similar to @bflad 's Set type. Can't do this in SDKv2, but parity w/ protocol.

[apparentlymart]

The tuple type kind is honestly rather odd and isn't something I'd generally expect folks to write in a type constraint... it's mainly there to fill in the missing spot that made our type system not a superset of JSON's, and used in dynamically-typed situations like the argument to jsonencode, or similar sorts of things like the kubernetes_manifest resource type in the hashicorp/kubernetes provider.

We did still include type constraint syntax for it in the language, more for completeness than anything else, and a similar "completeness" argument could apply here too, but I'd guess it's more likely that tuples will appear mainly as part of arguments that are dynamically-typed and so provider code will probably end up converting it immediately to []interface{} by reflection anyway. 🤔

[bookshelfdave]

We're going to close this for now. If there's a need for tuples at some point in the future, please create a new issue with the use case.

[github-actions]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.
If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.