Nested Tagged Unions
**TypeScript Version:** 2.5.2 **Code** ```ts type A = { type: "a", a: number } type B = { type: "b", b: number } type X = { type: A, a: string } type Y = { type: B, b: string } let x: X | Y if (x.type.type === "a") { x.a // Type Error } ``` **Expected behavior:** I would expect x to have type `X` inside the if-statement after disambiguating the nested tagged union types. **Actual behavior:**
Posted by ccorcos on Sep 26, 2017, 1:17 AM
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Related issues
- struct's lifetime requirements can be bypassed via covariant field assignment
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- Progressive FPS degradation appears to be related to dota2.com — blocking the domain prevents the performance loss
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- A concrete policy for backward compatibility until Godot 5.0
Raise real-world problems, find people facing the same issue, and discuss solutions.4,500 issues0 comments
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struct's lifetime requirements can be bypassed via covariant field assignment
Proposal to Reorganize the Moderation Team and Review Moderation Policies
Progressive FPS degradation appears to be related to dota2.com — blocking the domain prevents the performance loss
proposal: container/...: generic collection types
Better Custom Endpoint BYOK
A concrete policy for backward compatibility until Godot 5.0
New MTP models not supported
Tracking: 429 / Capacity Issues
Nested Tagged Unions
**TypeScript Version:** 2.5.2 **Code** ```ts type A = { type: "a", a: number } type B = { type: "b", b: number } type X = { type: A, a: string } type Y = { type: B, b: string } let x: X | Y if (x.type.type === "a") { x.a // Type Error } ``` **Expected behavior:** I would expect x to have type `X` inside the if-statement after disambiguating the nested tagged union types. **Actual behavior:**
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