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Improve the UX of reading tagged unions a smidge. (#449)
The page is a little narrow, and having to scroll on this horizontally isn't too nice. This fixes the UX for this specific part.
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1 changed files with 5 additions and 3 deletions
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@ -392,18 +392,20 @@ local account: Account = Account.new("Alexander", 500)
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Tagged unions are just union types! In particular, they're union types of tables where they have at least _some_ common properties but the structure of the tables are different enough. Here's one example:
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```lua
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type Result<T, E> = { type: "ok", value: T } | { type: "err", error: E }
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type Ok<T> = { type: "ok", value: T }
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type Err<E> = { type: "err", error: E }
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type Result<T, E> = Ok<T> | Err<E>
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```
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This `Result<T, E>` type can be discriminated by using type refinements on the property `type`, like so:
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```lua
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if result.type == "ok" then
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-- result is known to be { type: "ok", value: T }
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-- result is known to be Ok<T>
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-- and attempting to index for error here will fail
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print(result.value)
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elseif result.type == "err" then
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-- result is known to be { type: "err", error: E }
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-- result is known to be Err<E>
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-- and attempting to index for value here will fail
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print(result.error)
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end
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