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It's similar, but more inspired by C#'s "using declaration", an evolution of the using blocks, which are the C# version of try-with-resource: `using` declarations don't introduce their own block / scope.

The original proposal references all of Python's context manager, Java's try-with-resource, and C#'s using statement and declaration: https://github.com/tc39/proposal-explicit-resource-managemen...

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Only experience with C# using and Python context managers, but they always seemed like such an unsatisfying solution compared to C++/Rust style RAII. I mean, I get these are GC languages, but why can't just this happen at end of your regular scope? Why do you have to have these artificial new scopes?

That's what's neat about the simpler C# version (and this proposal): it's bound to whatever block it's in and doesn't need its own scope/indentation

using var stream = GetStream(); does not introduce new (lexical) scope, avoiding use means that the type system either has to understand move semantics (in case the stream is returned or move elsewhere, but then, what about sharing?) or have full-blown borrow checker which will emit drop.

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