ClrPro.DotNetLanguages.Proposals (nuget): .Net Languages improvement proposals code.       Contains:       - I(Async)CodeScopeExtension interfaces, generalizes using operator.       - I(Async)LifetimeExplicit, I(Async)LifetimeTerminable, I(Async)LifetimeObservable interfaces.       - using operator polyfill extension methods: Using, UsingAsync.
Keywords: using|IDisposable|IAsyncDisposable|Exception