> For the complete documentation index, see [llms.txt](https://ploegert.gitbook.io/til/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ploegert.gitbook.io/til/programmy/ml/reason/two-ways-to-find-an-item-in-a-list.md).

# Two Ways To Find An Item In A List

The `List` module has the typical `find` function that you'd expect any enumerable type to include. It has a very similar `find_opt` function as well. The difference is in the return types.

When using `List.find` you'll have to deal with the possibility of a `Not_found` exception.

```
switch (List.find(item => item.id == id, my_list)) {
| exception Not_found => print_endline("Not found!")
| item => print_endline("Found it: " ++ item.name)
}
```

The `List.find_opt` function has a more familiar interface that doesn't require you to know the details of what exceptions could arise. All you want to know is if it was found or *not*. This is achieved by having an `option('a)` return type.

```
switch (List.find_opt(item => item.id == id, my_list)) {
| None => print_endline("Not found!")
| Some(item) => print_endline("Found it: " ++ item.name)
}
```

See the [`List` module](https://reasonml.github.io/api/List.html) for more details.


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