Union types are sometimes able to override the properties: ```ts type Confused = {name: string | number} type Certain = Confused & {name: string}; const user: Certain = {}; user.name // string ``` but sometimes they can't ```ts type Confused = {name: string | Element} type Certain = Confused & {name: string}; const user: Certain = {}; user.name // (string | Element) & string ``` https://www.typescriptlang.org/play?#code/LAKALgngDgpgBAYQPYDsBmBXAzjAJnAXjgG8UBDAWxgC44swAnASxQHM4AfOAUQBsYqKMAF9QoSLEQwGYMi0KJUmHPgBkJclVr1mbYQG4xIAMap6cbNNoJpslkcsMAdJphA This is either a bug or a TS limitation, but perhaps it can be avoided: ```ts type Certain = Override ``` This is currently feasible with: ```ts type PreCertain = {name: string}; type Certain = Omit & PreCertain; ``` https://www.typescriptlang.org/play?#code/LAKALgngDgpgBAYQPYDsBmBXAzjAJnAXjgG8UBDAWxgC44swAnASxQHM4AfOAUQBsYqKMAF9QoSLDgAFBjAQwGYMi0IlyVWvWZthAbnHR48xcpSqA8hSZgAPMnTY8AGjgBrGBCRpps40pYAfHAAZD5yCv4o+iCgAMao9HCODLR+pqrEemIgyQB06jBAA I'm not sure if it's worth adding to type-fest, but I wanted to document it ## Upvote & Fund - We're using [Polar.sh](https://polar.sh/sindresorhus) so you can upvote and help fund this issue. - The funding will be given to active contributors. - Thank you in advance for helping prioritize & fund our backlog.

`Override<{a: number, b: number}, {a: string}>` for unions that override props from the previous object #429

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