Titian Cernicova-Dragomir

@tadhgmister I was thinking along the same line when reading this issue. You can forbid dynamic access altogether with a conditional type: ```ts type GetKnownKeys = G extends GuardedMap ?...

@tadhgmister Or an even simpler version that works for nested ifs as well: ```ts interface GuardedMap extends Map { has(k: S): this is (K extends S ? {} : {...

I know expression level syntax is a no-no, but how about: ```ts const MyComponent = ({ ... } : { a : string, b : number }) => { //...

Actually the more I think about `::` the more I like it 😁, but with a slightly different meaning. Let's not consider `::` as a new way to introduce a...

@pynnl that ship sailed a long time ago unfortunately.

@AnyhowStep It might be a conditional type hiding behind a type alias right now as well, that works under certain conditions and errors under others. Same rules should apply.

We generally don't look up any symbols beyond the current expression. So `Foo.A` could really be anything not necessarily an enum. Looking up the symbol in the same file is...

For computed properties we already allow this and error in TS if the type is not a late bindable computed property (ie it's not a property that can be a...

@RyanCavanaugh The fields associated with the accessor starts out as `null`, but nobody is allowed to set it to `null`: Something like ```ts class ProcessWrapper { #processId: number | null...

> > It was using `ts-expect-error` to suppress the error that now no longer exists (we switched to `ts-ignore` for now) > > Huh, I admit it never occurred to...