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fix: typos in "06-union-and-intersection-types" markdown #1116

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fix: typos in "06-union-and-intersection-types" markdown #1116

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8d2ca23
fix: type 'odd' to 'even'
kabrunko-dev May 7, 2024
2d30896
fix: typo '>=' to '>'
kabrunko-dev May 7, 2024
9a4509e
fix: typos
kabrunko-dev May 7, 2024
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10 changes: 5 additions & 5 deletions ...s/website/content/blog/fundamentals-v4/06-union-and-intersection-types/index.md
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Expand Up @@ -33,7 +33,7 @@ OneThroughFive | Evens => { 1, 2, 3, 4, 5, 6, 8 }
```

If you think about the assumptions we could make about a member of this set at random, we couldn't
be sure whether it's between 1 and 5, and we couldn't be sure whether it's odd.
be sure whether it's between 1 and 5, and we couldn't be sure whether it's even.

### Intersection types `&`

Expand Down Expand Up @@ -95,7 +95,7 @@ let evenOrLowNumber = 5 as Evens | OneThroughFive;
Union types often appear where control flow can produce a different value for different code paths.

For example, the `flipCoin()` function will return `"heads"` if a number selected
from `(0, 1)` is >= 0.5, or `"tails"` if <=0.5.
from `(0, 1)` is > 0.5, or `"tails"` if <=0.5.

```ts twoslash
function flipCoin() {
Expand Down Expand Up @@ -207,11 +207,11 @@ second.n
```

We can see that the autocomplete information for the first value suggests that it's
a string. This is because, regardles of whether this happens to be the specific `"success"`
a string. This is because, regardless of whether this happens to be the specific `"success"`
or `"error"` string, it's definitely going to be a string.

The second value is a bit more complicated -- only the `name` property is available to us.
This is because, both our "user info object, and instances of the `Error` class have a `name`
This is because, both our user info object, and instances of the `Error` class have a `name`
property whose value is a string.

Let's also look at our previous example involving `{1,2,3,4,5} | {2,4,6,8}` and consider how these `AND` and `OR` type operators describe the set of possible values, and the assumptions we can make about any given value in the set
Expand Down Expand Up @@ -244,7 +244,7 @@ printNumber(x)

There's some interesting asymmetry at play here. A `Evens | OneThroughFive` can accept a wide range of values, but because allows for this flexibility, it doesn't meet the type-checking requirements for most of the `print*` functions.

> *Essentially, **`|` means "anything in either set" in terms of the allowed values**, and because of this **only the behavior that's definitely present on every member of both sets is available to us**
> Essentially, **`|` means "anything in either set" in terms of the allowed values**, and because of this **only the behavior that's definitely present on every member of both sets is available to us**

### Narrowing with type guards

Expand Down