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Update 05-unions-literals-and-narrowing.md #56

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Update 05-unions-literals-and-narrowing.md #56

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2 changes: 1 addition & 1 deletion book-content/chapters/05-unions-literals-and-narrowing.md
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Expand Up @@ -380,7 +380,7 @@ This lets us call `toUpperCase` on `year` when it's a `string`, and `toFixed` on

However, anywhere outside of the conditional block the type of `year` is still the union `string | number`. This is because narrowing only applies within the block's scope.

For the sale of illustration, if we add a `boolean` to the `year` union, the first `if` block will still end up with a type of `string`, but the `else` block will end up with a type of `number | boolean`:
For the sake of illustration, if we add a `boolean` to the `year` union, the first `if` block will still end up with a type of `string`, but the `else` block will end up with a type of `number | boolean`:

```typescript
const getAlbumYear = (year: string | number | boolean) => {
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