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Fix variant design decisions #1024

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Merged
merged 2 commits into from
May 5, 2025
Merged

Fix variant design decisions #1024

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361de87
fix variant design decisions
zth May 4, 2025
0b14224
format
zth May 4, 2025
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43 changes: 31 additions & 12 deletions pages/docs/manual/v12.0.0/variant.mdx
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Original file line number Diff line number Diff line change
Expand Up @@ -762,13 +762,16 @@ Performance-wise, a variant can potentially tremendously speed up your program's

```js
let data = 'dog'
if (data === 'dog') {
...
} else if (data === 'cat') {
...
} else if (data === 'bird') {
...
function logData(data) {
if (data === 'dog') {
...
} else if (data === 'cat') {
...
} else if (data === 'bird') {
...
}
}
logData(data)
```

There's a linear amount of branch checking here (`O(n)`). Compare this to using a ReScript variant:
Expand All @@ -778,16 +781,32 @@ There's a linear amount of branch checking here (`O(n)`). Compare this to using
```res example
type animal = Dog | Cat | Bird
let data = Dog
switch data {
| Dog => Console.log("Wof")
| Cat => Console.log("Meow")
| Bird => Console.log("Kashiiin")
let logData = data => {
switch data {
| Dog => Console.log("Wof")
| Cat => Console.log("Meow")
| Bird => Console.log("Kashiiin")
}
}
logData(data)

```
```js
console.log("Wof");
function logData(data) {
switch (data) {
case "Dog" :
console.log("Wof");
return;
case "Cat" :
console.log("Meow");
return;
case "Bird" :
console.log("Kashiiin");
return;
}
}

var data = "Dog";
logData("Dog");
```

</CodeTab>
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